Among these automatic pool chlorinators, I’d name the Hayward CL200 In-Line Feeder the best overall for pool owners seeking a familiar, in-line tablet-feeder format, while the Pentair Rainbow 320 stands out for buyers who want a recognized in-line chlorine-and-bromine feeder design. For an off-line installation, the XtremepowerUS 9 lb Feeder offers a different fit that can suit plumbing layouts where an in-line unit is awkward. The central tradeoff is choosing between tablet feeders, which connect to pool plumbing, and the Intex QS200 saltwater system, which uses a different chlorination approach and suits compatible above-ground setups. Capacity, plumbing compatibility, and installation style matter more than a long feature list. Continue reading for the full breakdown and help matching a chlorinator to your pool.
Get pool and patio gear delivered free with Prime
- Fast, free delivery on millions of items
- Prime Video, Amazon Music and more included
- Member-only deals all year
Complete the kit
Key Takeaways
- Installation style separates the shortlist: In-line feeders such as the Hayward CL200 and Pentair Rainbow 320 connect directly to the return plumbing, while the XtremepowerUS and Hayward CL220EF off-line options use separate plumbing connections.
- A saltwater system is a different kind of choice: The Intex Krystal Clear QS200 is not a tablet feeder, so buyers should check pool-system compatibility before comparing it with the other products.
- Capacity needs to match maintenance habits: The 9 lb XtremepowerUS and Hayward CL220EF models are aimed at buyers who want larger feeder capacity, while compact designs such as the Pentair Rainbow 300 may suit smaller setups.
- Compatibility claims deserve close attention: The R171096 models are described as compatible alternatives to the Pentair Rainbow 320 or 320-style feeders, so buyers should verify dimensions and connection details rather than assume a fit.
- Brand familiarity and installation flexibility pull in different directions: Hayward and Pentair offer recognizable feeder formats, while off-line designs can be more practical when plumbing placement makes an in-line feeder inconvenient.
| XtremepowerUS Inline Automatic Pool Chlorinator for 3-Inch Tablets |  | Best Inline Pick for Small Pools | Model: 90157 | Installation: Inline in the pool return line | Tablet size: 3 inches | VIEW LATEST PRICE | See Our Full Breakdown |
| Intex Krystal Clear QS200 Saltwater Pool Chlorine System |  | Best Saltwater System for Very Small Pools | Model: QS200 | Part number: 26661EG | Pool capacity: Up to 2,200 gallons | VIEW LATEST PRICE | See Our Full Breakdown |
| Hayward CL200 In-Line Automatic Chlorine Feeder for Pools |  | Best for Flexible Tablet Dosing | Model: CL200 | Type: In-line automatic chemical feeder | Compatible tablets: Slow-dissolving trichlor or bromine tablets | VIEW LATEST PRICE | See Our Full Breakdown |
| Hayward CL200EF Automatic Chlorine Feeder for In-Ground Pools |  | Best Offline Feeder for In-Ground Pools | Model: CL200EF | Type: Offline automatic chlorine feeder | Capacity: Up to 9 lb of chlorine tablets | VIEW LATEST PRICE | See Our Full Breakdown |
| XtremepowerUS Automatic Off-Line Pool Chlorinator Feeder, 9 lb Capacity |  | Best Off-Line Value for Small Pools | Model: 90156 | Type: Off-line automatic chlorinator | Capacity: 9 lbs | VIEW LATEST PRICE | See Our Full Breakdown |
| R171096 Compatible 320 Automatic In-Line Chlorine and Bromine Feeder |  | Best for Flexible Tablet Capacity | Model: 320 | Manufacturer part number: R171096 | Brand: CAtArt | VIEW LATEST PRICE | See Our Full Breakdown |
| Pentair Rainbow 300 Automatic Pool and Spa Feeder |  | Best for Enclosed-System Operation | Series: 300 | System: Completely enclosed | Venting: No special venting required | VIEW LATEST PRICE | See Our Full Breakdown |
| Hayward CL100 Automatic Chlorine Feeder |  | Best for Adjustable Tablet Feeding | Brand: Hayward | Model: CL100 | Tablet diameter: 3 inches | VIEW LATEST PRICE | See Our Full Breakdown |
| Hayward CL220EF Off-Line Chemical Feeder, 9 lb Capacity |  | Best Off-Line Pick | Brand: Hayward | Model: CL220EF | Feeder type: Off-line automatic chemical feeder | VIEW LATEST PRICE | See Our Full Breakdown |
| Pentair Rainbow 320 Automatic In-Line Chlorine/Bromine Feeder |  | Best Established-Brand In-Line Pick | Brand: Pentair | Model: R171096 | Compatible use: Pools and spas | VIEW LATEST PRICE | See Our Full Breakdown |
| U.S. Pool Supply In-Line Automatic Chlorine Feeder, 9 lb |  | Best for Easy Chemical-Level Checks | Chemical capacity: 9 lb (4 kg) | Compatible chemicals: Slow-dissolving trichlor chlorine or bromine tablets or sticks | Installation type: In-line | VIEW LATEST PRICE | See Our Full Breakdown |
| Swimline Hydrotools 8750 In-Line Automatic Chlorine Feeder |  | Best for Above-Ground and In-Ground Pool Flexibility | Model: 8750 | Type: In-line automatic chlorine feeder | Capacity: 9.0 lb | VIEW LATEST PRICE | See Our Full Breakdown |
| R171096 Automatic In-Line Pool Chlorinator, Compatible with Pentair Rainbow 320 |  | Best for Rainbow 320 Replacements | Model: R171096 | Compatibility: Pentair R171096 and Rainbow 320 | Material: ABS plastic | VIEW LATEST PRICE | See Our Full Breakdown |
More Details on Our Top Picks
XtremepowerUS Inline Automatic Pool Chlorinator for 3-Inch Tablets
For owners of an above-ground or small in-ground pool who want tablet dosing built into the return line, this XtremepowerUS feeder offers a straightforward setup. Its 9-pound tank holds a substantial supply for its intended pool size, while the adjustable dial lets owners change the feed rate rather than relying on a fixed output. Compared with the XtremepowerUS Automatic Off-Line Pool Chlorinator Feeder, this model installs inline, so it suits plumbing layouts where an off-line connection is less convenient. That choice also means the feeder sits directly in the return path. It accepts 3-inch slow-dissolving tablets and can dispense chlorine or bromine, but tablets are not included. Its small-pool focus is a meaningful limit: buyers with larger pools should choose a feeder rated for their system instead.
Pros:- 9-pound tank reduces how often tablets need replenishing.
- Adjustable dial gives owners control over the tablet feed rate.
- Accepts 3-inch chlorine or bromine tablets.
- UV-resistant resin is suited to outdoor pool equipment.
Cons:- Intended for above-ground and small in-ground pools, limiting its fit for larger systems.
- Inline installation places the feeder in the pool return line.
- Tablets are sold separately.
Best for: Owners of above-ground or small in-ground pools who want an adjustable inline feeder with a 9-pound tablet reservoir.
Not ideal for: Owners of larger pools or anyone who wants to avoid placing a chemical feeder directly in the return line.
- Model:90157
- Installation:Inline in the pool return line
- Tablet size:3 inches
- Tank capacity:9 lbs
- Feed control:Adjustable dial
- Maximum pressure:50 PSI
- Material:Heavy-duty, UV-resistant resin
Our verdict“Choose this XtremepowerUS model for adjustable inline tablet dosing in a smaller pool, but look elsewhere if your pool needs a higher-capacity system.”
Intex Krystal Clear QS200 Saltwater Pool Chlorine System
The Intex QS200 suits buyers who want to make chlorine from salt rather than load a tablet feeder. It is designed for above-ground pools up to 2,200 gallons, with a 24-hour timer for scheduled operation and a 10-hour self-cleaning cycle. That makes its approach quite different from the Hayward CL200 In-Line Automatic Chlorine Feeder, which dispenses slow-dissolving tablets and depends on an existing pump and filter system. The QS200 is a better match for owners who prefer saltwater sanitation, but its narrow pool-capacity range limits where it can be used. It also requires a compatible filter pump operating at 300–1,000 GPH, and that pump is sold separately. HydroAeration adds circulation and water-clarity support, but this is not a universal replacement for other pool care.
Pros:- Uses salt to sanitize instead of relying on tablet loading.
- 24-hour timer supports scheduled operation.
- 10-hour self-cleaning cycle is built into the system.
- HydroAeration supports circulation, filtration, and water clarity.
Cons:- Limited to pools up to 2,200 gallons.
- Requires a compatible 300–1,000 GPH filter pump, sold separately.
- Saltwater generation is a different setup from the tablet-based feeders in this roundup.
Best for: Above-ground pool owners with pools up to 2,200 gallons who prefer saltwater chlorine generation and have a compatible filter pump.
Not ideal for: Owners of larger pools or buyers seeking a simple tablet feeder that works with their existing pool plumbing.
- Model:QS200
- Part number:26661EG
- Pool capacity:Up to 2,200 gallons
- Required pump flow rate:300–1,000 GPH
- Timer:24-hour
- Self-cleaning cycle:10 hours
- Warranty:2-year limited warranty
Our verdict“Pick the QS200 for a compatible small above-ground pool if you want saltwater chlorine generation rather than tablet feeding.”
Hayward CL200 In-Line Automatic Chlorine Feeder for Pools
The Hayward CL200 is a sensible choice for pool or spa owners who want an inline feeder with adjustable output and compatibility with slow-dissolving trichlor or bromine tablets. Its threaded cover and safety catch make access more controlled, while the Viton seal and ABS body are intended for chemical-feeder duty. Compared with the XtremepowerUS Inline Automatic Pool Chlorinator, the CL200’s product information highlights use with large or small tablets rather than specifying a 3-inch-only tablet size, giving buyers a different compatibility profile. It does not offer the stated 9-pound capacity of that XtremepowerUS model, so refill planning may matter more. This feeder also depends on a compatible pump and filter system, and it is not the pick for someone who wants a saltwater generator or a standalone dosing setup.
Pros:- Adjustable dial allows feed-rate changes.
- Compatible with slow-dissolving trichlor or bromine tablets.
- Threaded cover and safety catch support more controlled access.
- ABS body and Viton seal are designed for chemical-feeder use.
Cons:- Requires a compatible pool or spa pump and filter system.
- Designed for slow-dissolving tablets rather than saltwater chlorine generation.
- The provided product data does not state a tank capacity.
Best for: Pool and spa owners with a compatible pump and filter who want an adjustable inline feeder for slow-dissolving trichlor or bromine tablets.
Not ideal for: Buyers seeking saltwater sanitation, a standalone system, or a clearly specified large-capacity tablet reservoir.
- Model:CL200
- Type:In-line automatic chemical feeder
- Compatible tablets:Slow-dissolving trichlor or bromine tablets
- Feed control:Adjustable dial
- Body material:ABS
- Seal material:Viton
Our verdict“Choose the CL200 when you want an adjustable inline feeder with broad tablet-size compatibility and already have compatible pool plumbing.”
Hayward CL200EF Automatic Chlorine Feeder for In-Ground Pools
For residential in-ground pool owners whose plumbing suits an off-line configuration, the CL200EF pairs automatic tablet dosing with a capacity of up to 9 pounds. Its adjustable output dial lets owners regulate delivery, and the larger reservoir can reduce how often they need to open the feeder compared with a smaller-capacity option such as the Hayward CL200, whose supplied specs do not list a capacity. The key difference is installation: this is not an inline replacement, so buyers need to plan for an off-line plumbing connection and follow the manufacturer’s installation guidance. That makes it less appealing to anyone who wants a simple swap into an existing return line. The product data focuses on chlorine tablets for in-ground pools, so it is a narrower fit than feeders explicitly described for chlorine or bromine use.
Pros:- Holds up to 9 pounds of chlorine tablets.
- Adjustable dial allows output regulation.
- Off-line configuration suits compatible in-ground pool plumbing.
- Automates tablet dosing during pool operation.
Cons:- Requires an off-line plumbing configuration.
- Installation should follow manufacturer recommendations.
- Product information does not specify bromine compatibility.
Best for: Residential in-ground pool owners who need an off-line chlorine feeder with a substantial tablet capacity and adjustable output.
Not ideal for: Above-ground pool owners or anyone whose plumbing calls for an inline feeder rather than an off-line installation.
- Model:CL200EF
- Type:Offline automatic chlorine feeder
- Capacity:Up to 9 lb of chlorine tablets
- Installation:Offline plumbing configuration
- Control:Adjustable sanitizer output dial
- UPC:610377003827
Our verdict“Choose the CL200EF if your in-ground pool can accommodate off-line plumbing and you want a 9-pound chlorine tablet feeder.”
XtremepowerUS Automatic Off-Line Pool Chlorinator Feeder, 9 lb Capacity
This XtremepowerUS feeder makes the most sense for owners of above-ground or small in-ground pools who want a large tablet reservoir without putting the feeder directly in the return line. Its off-line installation can help avoid adding the feeder body to the main water path, while a dial knob adjusts the feed rate. Like the Hayward CL200EF, it holds up to 9 pounds, but this model explicitly supports slow-dissolving trichlor chlorine or bromine tablets up to 3 inches. That flexibility is useful for buyers choosing between those sanitizers. The tradeoff is its stated small-pool focus, which rules it out for many larger systems. It also requires the right off-line plumbing arrangement, and tablets are sold separately.
Pros:- 9-pound capacity reduces the frequency of tablet refills.
- Off-line installation helps keep the feeder out of the main return path.
- Adjustable dial controls tablet feed rate.
- Accepts slow-dissolving trichlor chlorine or bromine tablets up to 3 inches.
Cons:- Intended for above-ground and small in-ground pools.
- Requires off-line plumbing installation.
- Tablets are sold separately.
Best for: Owners of above-ground or small in-ground pools who want an off-line feeder for 3-inch chlorine or bromine tablets.
Not ideal for: Owners of larger pools or anyone who needs an inline feeder or a system that generates chlorine from salt.
- Model:90156
- Type:Off-line automatic chlorinator
- Capacity:9 lbs
- Tablet size:Up to 3 inches
- Compatible tablets:Slow-dissolve trichlor chlorine or bromine
- Maximum pressure:50 PSI
- Material:Heavy-duty resin
Our verdict“Choose this model for adjustable off-line chlorine or bromine dosing in a small pool, but skip it if your pool needs a larger-scale feeder.”
R171096 Compatible 320 Automatic In-Line Chlorine and Bromine Feeder
The standout here is choice of tablet size and sanitizer: the feeder holds up to 11 large or 98 small chlorine or bromine tablets, making it more adaptable than the Hayward CL100, which is specified for 3-inch tablets. Its listed pool-capacity ranges also vary by feed position, so buyers should match the installation orientation to their pool rather than treating one range as universal. The package includes 2-inch PVC accessories and 1½-inch adapters, which can simplify fitting it to common return-line plumbing. A widened gasket and upgraded control valve are intended to help limit leaks, but this is still an in-line unit that needs monthly cleaning. Compared with the Pentair Rainbow 320, it offers similar stated tablet capacity and adapters, but the supplied product details provide less assurance about brand support and warranty.
Pros:- Accepts chlorine or bromine tablets in large or small sizes
- Capacity is stated as up to 11 large or 98 small tablets
- Includes fittings for 2-inch and 1½-inch plumbing
- Widened gasket and upgraded control valve are designed to improve sealing
Cons:- Requires regular cleaning, with monthly cleaning recommended
- Pool-capacity range depends on feed position, which buyers must account for during installation
- Product details do not state a warranty
Best for: Pool or spa owners who want an in-line feeder that accepts large or small chlorine and bromine tablets and need adapters for 1½-inch plumbing.
Not ideal for: Owners who prefer an established-brand option with a stated warranty, or anyone unwilling to clean a feeder regularly.
- Model:320
- Manufacturer part number:R171096
- Brand:CAtArt
- Tablet capacity:Up to 11 large or 98 small chlorine or bromine tablets
- Pool capacity:6,500–27,000 gallons for bottom feed; 18,000–70,000 gallons for top feed
- Included fittings:2-inch PVC sliding accessories and 1½-inch adapters
- Maintenance:Regular cleaning recommended monthly
Our verdict“Choose this feeder if tablet-size flexibility and included plumbing adapters matter more than a clearly stated warranty or established-brand support.”
Pentair Rainbow 300 Automatic Pool and Spa Feeder
The Rainbow 300 earns its place for buyers who prioritize a fully enclosed feeder and want a model that requires no special venting. Its NSF listing gives buyers a documented certification detail that is absent from the other options in this group. Compared with the Hayward CL100, whose description emphasizes adjustable feed control and tablet access, the Rainbow 300’s supplied details focus more on containment than on dosing controls or capacity. That makes it harder to judge how often it needs refilling or how well its output can be tuned for a particular pool. The main installation caveat is practical: unions are not included, so buyers may need to source compatible plumbing parts separately. I’d favor it when enclosure and certification are the priority, but choose a model with clearer capacity and control details when dosing flexibility is central.
Pros:- Completely enclosed system
- Does not require special venting
- NSF listed
- Designed for both pool and spa use
Cons:- Unions are not included
- Supplied product data does not state tablet capacity
- Supplied product data does not describe adjustable feed controls
Best for: Pool and spa owners who prioritize an enclosed feeder, do not want special venting requirements, and value an NSF-listed option.
Not ideal for: Buyers who need a stated tablet capacity, detailed dosing-control information, or a package that includes unions.
- Series:300
- System:Completely enclosed
- Venting:No special venting required
- Unions:Not included
- Certification:NSF listed
- Intended use:Pools and spas
Our verdict“Pick the Rainbow 300 when enclosed operation and NSF listing lead your priorities, but compare capacity and dosing details before choosing it over the Hayward CL100.”
Hayward CL100 Automatic Chlorine Feeder
The CL100 is the clearest fit for buyers who want to adjust the feed rate rather than choose a feeder based mainly on tablet capacity or enclosure. It works with a pool or spa pump and filter system, and its threaded cover and release catch provide a defined route for refilling and securing the lid. That makes its operating details more explicit than the Pentair Rainbow 300, whose supplied information does not specify adjustable feed control. The tradeoff is that the CL100 depends on an existing pump-and-filter setup and is specified for 3-inch tablets, limiting flexibility compared with the tablet-size options listed for the compatible 320 feeder. Its 50 gpm flow-rate specification may help buyers check system compatibility, but it does not replace confirming fit with their plumbing and equipment.
Pros:- Adjustable feed control lets owners tune dispensing
- Threaded cover provides access for adding tablets
- Release catch adds security at the cover
- Designed to operate with a pool or spa pump and filter system
Cons:- Requires a pump and filter system
- Uses 3-inch-diameter tablets, limiting tablet-size choice
- Above-ground installation specification may not suit every plumbing layout
Best for: Pool owners with a compatible pump-and-filter system who want adjustable feeding and use 3-inch chlorine or bromine tablets.
Not ideal for: Owners without a pump-and-filter system or those who need a feeder that accepts smaller tablet sizes.
- Brand:Hayward
- Model:CL100
- Tablet diameter:3 inches
- Flow rate:50 gpm
- Material:Plastic
- Dimensions:16 × 8 × 8 inches
- Installation:Above ground
- Operation:Requires a pool or spa pump and filter system
Our verdict“Choose the CL100 if your system supports it and adjustable feeding with 3-inch tablets is more useful than broad tablet-size compatibility.”
Hayward CL220EF Off-Line Chemical Feeder, 9 lb Capacity
Unlike the in-line models in this group, the CL220EF is an off-line feeder, giving it a different installation role for pools where an in-line unit is not the preferred fit. Its 9 lb capacity offers a clear measure of how much tablet or stick product it can hold, while the enclosed ABS body and Viton seal are designed to contain the chemical supply. The Easy Lok threaded cover also gives owners a defined access point for refilling. Compared with the Pentair Rainbow 320, which installs in the return line and includes adapters for two common pipe sizes, this Hayward model is the alternative for buyers specifically seeking off-line placement. That placement still requires suitable plumbing connections, and the product details do not say tablets or sticks are included. Check compatibility with your PVC layout before choosing it.
Pros:- Off-line design offers an alternative to return-line installation
- Holds up to 9 lb of tablets or sticks
- Enclosed ABS body and Viton seal are designed for chemical containment
- Easy Lok threaded cover provides access for refilling
Cons:- Off-line installation must suit the existing plumbing layout
- Tablets or sticks are not stated as included
- Product details do not list unions or specific fitting sizes
Best for: Pool owners who need an off-line feeder for an in-ground or above-ground pool and want a stated 9 lb capacity.
Not ideal for: Buyers who need an in-line return-line feeder or want included tablets, sticks, or clearly listed installation fittings.
- Brand:Hayward
- Model:CL220EF
- Feeder type:Off-line automatic chemical feeder
- Capacity:9 lb
- Body material:ABS
- Seal material:Viton
- Item weight:4 lb
- Compatible installation:Fits most PVC plumbing; for in-ground and above-ground pools
Our verdict“Select the CL220EF if you specifically need an off-line feeder with a 9 lb capacity, rather than the in-line layout of the Rainbow 320.”
Pentair Rainbow 320 Automatic In-Line Chlorine/Bromine Feeder
The Rainbow 320 is a straightforward choice for buyers who want an in-line chlorine or bromine feeder with clearly stated tablet capacity and plumbing sizes. It holds up to 11 large or 98 small tablets and installs in a new or existing return line, with adapters for 1½-inch connections included alongside the 2-inch slip fitting. That puts it close to the compatible R171096 model, but the Pentair listing also specifies a one-year warranty, which can make its support terms easier to evaluate. Both versions still need an appropriate return-line setup, and the Rainbow 320 does not include unions. Its product details also do not give a pool-capacity range, unlike the compatible 320 listing. I’d choose this model when brand identity and stated warranty matter more than having a published capacity range for a particular feed position.
Pros:- Accepts chlorine or bromine tablets
- Holds up to 11 large or 98 small tablets
- Includes a 2-inch slip fitting and adapters for 1½-inch connections
- Can install in a new or existing return line and has a one-year warranty
Cons:- Unions are not included
- Requires a compatible return-line installation
- Product details do not provide a pool-capacity range
Best for: Pool or spa owners seeking a branded in-line feeder for chlorine or bromine tablets, with adapters for 1½-inch plumbing and a stated warranty.
Not ideal for: Buyers who need an off-line installation, included unions, or a stated pool-capacity range to guide sizing.
- Brand:Pentair
- Model:R171096
- Compatible use:Pools and spas
- Tablet capacity:Up to 11 large or 98 small tablets
- Fitting:2-inch slip PVC with adapters for 1½-inch connections
- Installation:Return line; no special venting required
- Item weight:4.5 pounds
- Warranty:1 year
Our verdict“Choose the Rainbow 320 for a branded in-line feeder with flexible tablet capacity and a stated warranty, provided you can source unions if needed.”
U.S. Pool Supply In-Line Automatic Chlorine Feeder, 9 lb
The transparent easy-lock lid gives this feeder a practical advantage over opaque options such as the Swimline Hydrotools 8750: you can check the remaining tablets without opening the unit. Its 9 lb capacity and adjustable dial suit owners who want to regulate tablet delivery while keeping a substantial supply in the plumbing line. The included fittings and lid wrench also make setup and routine opening less of a parts hunt. It accepts slow-dissolving trichlor or bromine tablets and sticks, but the chemicals are not included. Like the Hydrotools, it needs an in-line plumbing connection and a working circulation system, so it is not a standalone chlorination option. I’d choose it for visibility and included accessories, not for a no-plumbing setup.
Pros:- Transparent lid makes remaining tablets easy to check
- Adjustable dial lets owners regulate chemical feed
- Holds up to 9 lb of compatible tablets or sticks
- Includes installation accessories and a lid wrench
Cons:- Requires installation in the pool plumbing
- Trichlor or bromine tablets and sticks are not included
Best for: Pool owners with in-line plumbing who want to monitor tablet levels through a clear lid and adjust chemical feed.
Not ideal for: Owners without compatible pool plumbing or those seeking a complete chemical-start kit, since installation is in-line and tablets or sticks are sold separately.
- Chemical capacity:9 lb (4 kg)
- Compatible chemicals:Slow-dissolving trichlor chlorine or bromine tablets or sticks
- Installation type:In-line
- Material:ABS plastic
- Feed control:Adjustable dial control valve
- Cover:Transparent easy-lock cover with O-ring seal
- Included accessories:Installation accessories, instructions, and lid wrench
- Compatible chlorinator:Hayward CL200
Our verdict“Choose this feeder if visible chemical levels and included installation tools matter more than avoiding in-line plumbing work.”
Swimline Hydrotools 8750 In-Line Automatic Chlorine Feeder
The Hydrotools 8750 is a straightforward pick for owners who want an in-line feeder that is specified for both above-ground and in-ground pools. Its 9 lb capacity and adjustable output put it in the same general range as the U.S. Pool Supply feeder, but the Hydrotools emphasizes reinforced thermoplastic construction designed to resist UV exposure and corrosion rather than a transparent lid for checking tablet levels. That makes it a reasonable fit for installations where material durability is the priority, though the available details do not list included installation accessories. It feeds through the existing pump and filter system, so it cannot operate independently of circulation or plumbing. Compared with saltwater systems such as the Intex Krystal Clear QS200, it is a tablet-feeder approach, not a chlorine-generation system.
Pros:- Specified for above-ground and in-ground pools
- Adjustable output helps regulate chlorine delivery
- 9 lb capacity provides room for a supply of chlorine
- Double-reinforced thermoplastic is designed to resist UV exposure and corrosion
Cons:- Requires connection to pool plumbing and a working pump and filter system
- Product details do not specify included installation accessories
- No transparent lid feature is listed for checking remaining tablets
Best for: Owners of above-ground or in-ground pools with existing circulation plumbing who want an adjustable tablet feeder built for outdoor exposure.
Not ideal for: Pool owners seeking a standalone chlorination system or those unwilling to connect a feeder to their pump and filter plumbing.
- Model:8750
- Type:In-line automatic chlorine feeder
- Capacity:9.0 lb
- Output:Adjustable
- Compatibility:Above-ground and in-ground pools
- Material:Double-reinforced thermoplastic
- System connection:Connects to pool plumbing and uses an existing pump and filter system
Our verdict“Pick the Hydrotools 8750 if you need an adjustable in-line feeder for either pool type and value UV- and corrosion-resistant construction.”
R171096 Automatic In-Line Pool Chlorinator, Compatible with Pentair Rainbow 320
For a feeder replacement, compatibility matters more than broad pool-type claims, and this model is specifically listed for the Pentair R171096 and Rainbow 320. Its capacity of up to 11 large or 98 small tablets and stated pool range of 6,500–70,000 gallons make it the highest-capacity option in this three-product group by tablet count. The included 2-inch slip fittings, 1.5-inch adapters, and drain plug add practical help for installation and cleaning. Compared with the U.S. Pool Supply feeder, this unit offers a stated pool-size range and replacement fit, but it lacks that model’s transparent lid for quick level checks. Its compatibility is narrow, and the plumbing must match; buyers should verify the existing feeder and pipe connections before choosing it.
Pros:- Designed as a replacement for Pentair R171096 and Rainbow 320 feeders
- Holds up to 11 large or 98 small tablets
- Includes 2-inch PVC slip fittings and 1.5-inch adapters
- Drain plug supports cleaning, and flow control is adjustable
Cons:- Compatibility is limited to the specified feeder models
- Requires compatible pool plumbing for installation
- Opaque enclosed body does not offer the U.S. Pool Supply feeder’s transparent level check
Best for: Owners replacing a Pentair R171096 or Rainbow 320 feeder who need adjustable flow control and supplied plumbing adapters.
Not ideal for: Pool owners with other feeder models or incompatible plumbing, since the stated fit is limited to Pentair R171096 and Rainbow 320 replacements.
- Model:R171096
- Compatibility:Pentair R171096 and Rainbow 320
- Material:ABS plastic
- Tablet capacity:Up to 11 large or 98 small tablets
- Pool size range:6,500–70,000 gallons
- Flow control:Adjustable
- Installation fittings:2-inch PVC slip fittings and 1.5-inch adapters
- Warranty:12 months
Our verdict“Choose this replacement when your pool already uses a Pentair R171096 or Rainbow 320 and its plumbing connections match.”
How We Picked
I compared these 13 automatic pool chlorinators by the decisions that most affect ownership: whether a product is an in-line feeder, off-line feeder, or saltwater system; what pool and plumbing setup it is intended to fit; and whether its stated capacity aligns with a buyer’s maintenance routine. I also considered usability, likely installation complexity, construction and maintenance needs, and how clearly compatibility is described. A chlorinator that cannot suit a pool’s plumbing or system type is a poor match regardless of its capacity.
The ranking gives priority to practical fit and versatility over headline claims. The Hayward CL200 leads as a straightforward in-line choice, while the Pentair Rainbow 320 earns a strong place for its chlorine-and-bromine feeder format. Larger off-line models rank well for plumbing flexibility and capacity, but are not the best fit for every pool. The Intex QS200 is included as a distinct saltwater option rather than treated as interchangeable with tablet feeders; compatible equipment and pool type shape its place in the lineup. Compatible replacement-style feeders rank lower when buyers need to verify fit more carefully.
Factors to Consider When Choosing Automatic Pool Chlorinators
Before choosing a feeder, I’d start with the pool’s equipment and the way you want to manage sanitation—not with capacity alone. These products include several installation formats and one saltwater system, so the right choice depends on your plumbing, pool type, and willingness to handle tablets or system upkeep.
Match the chlorinator type to your pool system
Tablet feeders and saltwater systems do not perform the same job in the same way, so compare options within the correct category first. An in-line or off-line feeder meters chlorine or bromine tablets into circulating water; the Intex QS200 is a saltwater chlorine system intended for compatible setups. Check the pool manufacturer’s guidance and existing equipment before buying, especially for above-ground pools with proprietary connections. A common mistake is treating “automatic” as proof that a unit will work with any pool. If your goal is to avoid handling tablets, a saltwater system may appeal, but it brings different installation and upkeep needs. If you already use tablets, a feeder is the more direct match.
Choose in-line or off-line based on plumbing access
An in-line feeder sits in the pool’s return plumbing, which can make for a direct installation when there is room and the plumbing layout supports it. An off-line feeder connects through separate lines, giving some owners more placement flexibility when a main-line installation is inconvenient. That flexibility can involve additional tubing and connection points, so it is not automatically the simpler option. Before ordering, measure the available space and identify the plumbing material, pipe size, and flow direction. Do not assume an existing feeder’s footprint or connections match a replacement just because the product names are similar. A small amount of advance checking can prevent a unit that is difficult to install or service.
Treat capacity as a maintenance interval, not a performance rating
A larger tablet chamber can mean fewer refills, but it does not tell you how much chlorine your pool needs or how quickly tablets will be used. Pool volume, sunlight, water temperature, swimming frequency, and tablet size all affect consumption. A 9 lb feeder may suit someone who prefers less frequent loading, yet it can be excessive for a small pool or a low-use season. Smaller feeders can be easier to fit and maintain, but may call for more frequent checks. Avoid choosing by capacity alone: make sure the feeder can be adjusted to your pool’s needs and that you will still test the water regularly. Automatic dosing helps deliver sanitizer; it does not replace water testing.
Check compatibility before buying a replacement-style feeder
Products described as compatible with a Pentair Rainbow 320-style feeder may not share every dimension, fitting, or service part with the original. Compare the existing unit’s model information, connection layout, and installation space against the replacement’s specifications. If you are replacing a damaged feeder, confirm which parts are included rather than assuming valves, tubing, or fittings come in the box. This matters even more when moving between in-line and off-line formats, since the plumbing work can differ. A compatible label is a useful starting point, not a substitute for checking measurements. When exact fit is uncertain, a feeder from the same system family may reduce guesswork.
Factor in chemical handling and routine service
Tablet feeders keep chemicals contained during normal dosing, but loading and cleaning still require careful handling and the manufacturer’s safety directions. Think about whether the lid is accessible, whether the unit can be isolated for service, and how comfortably you can reach it without contacting nearby equipment. Stagnant chemical solution and residue can make maintenance unpleasant, so plan for safe shutdown and servicing rather than treating the feeder as maintenance-free. Also check whether your routine uses chlorine or bromine, since not every pool setup is suited to the same sanitizer. Buyers who want fewer tablet-handling steps may prefer to investigate a compatible saltwater approach, while tablet users may value a familiar feeder with straightforward access. Do not mix chemical types or follow dosing assumptions across different systems.
Pay for fit and support, not just a bigger chamber
A premium choice makes sense when it solves a real problem: an established brand ecosystem, a better match for existing plumbing, or a design that suits your service routine. A less expensive compatible-style option may be attractive when replacing a familiar feeder, but a lower upfront commitment can be offset by extra fit checks or uncertainty about parts. Larger capacity is useful only if it suits your pool and schedule, while a more complex system is not an upgrade if you prefer simple tablet dosing. Check installation instructions, replacement-part availability, and the supplier’s compatibility information before deciding. For a new installation, it can be worth prioritizing clear guidance and a suitable plumbing format over maximum capacity. For a direct replacement, exact fit may matter more than brand breadth.
Frequently Asked Questions
Can I replace an existing Pentair Rainbow 320 with an R171096 compatible feeder?
It may be a candidate, but I would not rely on the compatibility wording alone. Compare the existing feeder’s connections, dimensions, and mounting space with the replacement’s listed specifications before ordering. Check whether you are replacing an in-line or off-line setup, since similar model references do not guarantee the same installation format. Also confirm which fittings and service parts are included. If the existing unit has a readable model label, use that information to verify the match.
Should I choose an in-line or off-line automatic feeder for a retrofit?
Start by looking at the available space and the current return plumbing. An in-line feeder can be a clean fit when there is a suitable section of pipe and room to service the lid. An off-line feeder may help when cutting into the main line is difficult or the installation needs more flexibility, though it adds separate connections and tubing. Check flow direction, pipe dimensions, and manufacturer installation requirements before choosing. For a retrofit, the easiest option is usually the one that matches the existing plumbing plan rather than the one with the larger chamber.
Is the Intex QS200 interchangeable with a tablet chlorinator?
No: the QS200 is a saltwater chlorine system, while the other feeder-style products dispense sanitizer tablets through pool plumbing. They serve a related sanitation goal but use different equipment and maintenance routines. Compatibility with the pool and its circulation system is a first-order requirement, so check Intex’s specifications for your exact setup. Do not buy it as a direct substitute for a tablet feeder without confirming the pool supports the system. If you already have a tablet routine and want to keep it, compare the in-line and off-line feeders instead.
Does a 9 lb feeder mean I can leave the pool unattended longer?
Not by itself. A larger chamber can reduce how often you reload tablets, but sanitizer use varies with pool size, weather, water temperature, and how often the pool is used. Automatic feeding also does not measure water chemistry or respond to every change in demand. You still need to test the water and adjust the feeder according to its instructions. If you expect to be away, have someone check the pool rather than treating chamber capacity as a substitute for monitoring.
Can I use a chlorine feeder with bromine tablets?
Only if the feeder’s manufacturer specifies that it supports bromine and the rest of your pool setup is appropriate for that sanitizer. Some products in this roundup are described for chlorine and bromine, while others are presented as chlorine feeders. Do not assume that a similar-looking chamber makes the chemicals interchangeable. Follow the product instructions and keep chemical types separate during loading and maintenance. If you are changing sanitizer, check the pool equipment and water-care guidance before using the same feeder.
Conclusion
For most buyers seeking a conventional tablet feeder, I’d choose the Hayward CL200 as the best overall starting point because its in-line format makes sense for a compatible return-plumbing setup. The XtremepowerUS 9 lb off-line feeder is my best value-style pick for owners who need a larger chamber and prefer an off-line layout, while the Pentair Rainbow 320 is my best premium-style choice for buyers prioritizing a recognized in-line chlorine-and-bromine feeder format. For beginners, I’d favor the feeder that matches existing plumbing and has the clearest installation instructions rather than adding complexity; the Hayward CL200 is a sensible candidate when the pool supports it. For compatible Intex above-ground pools, the QS200 is the specific saltwater option, not a direct tablet-feeder substitute. If plumbing access is the main challenge, compare the Hayward CL220EF and XtremepowerUS off-line designs; if replacing a 320-style unit, verify the R171096 model’s exact fit before buying.
Halloween Picks
halloween
As an affiliate, we earn on qualifying purchases.
