Chlorine tablets in a skimmer will damage your pool equipment and create uneven chlorine levels
You should not put chlorine tablets directly in your skimmer basket. Chlorine tablets are made of calcium hypochlorite or trichlor, both highly acidic and corrosive. When tablets sit in the skimmer, they dissolve slowly in a concentrated area, eating away at the skimmer's plastic housing, the pump, and the filter. The acid also damages metal parts and can crack concrete pool decks if water splashes out.
Beyond equipment damage, tablets in the skimmer create a chlorine concentration spike in one spot rather than distributing the chemical evenly across the pool. This uneven distribution means some areas get over-chlorinated while others stay under-chlorinated, making it harder to keep your water balanced and safe.
Key Takeaways
- Chlorine tablets dissolve into a corrosive acid that eats through skimmer plastic, pump seals, and filter components.
- The skimmer is designed to catch leaves and debris, not to hold chemical tablets, and the concentrated acid damages its housing.
- A floater or feeder dispenser spreads chlorine evenly throughout the pool instead of concentrating it in one spot.
- If your skimmer has already held tablets, inspect the pump and filter for cracks or discoloration and have a professional check for internal damage.
How chlorine tablets damage skimmers and pumps
Chlorine tablets are designed to dissolve slowly, but only when they are in the right environment. A skimmer basket is not that environment. The plastic housing of a skimmer is not rated to withstand the acid created as tablets break down. Over days or weeks, you will see white or cloudy spots on the inside of the skimmer, cracks in the plastic, or a chalky residue—all signs the acid is eating through.
The damage spreads downstream. Water carrying the concentrated chlorine solution flows directly from the skimmer into your pump. Pump seals are rubber and plastic; chlorine acid corrodes both. A corroded seal leaks, and a leaking pump loses prime and stops circulating water. The filter gets the same treatment—the concentrated solution damages the filter media and can crack the tank itself if it is made of fiberglass or plastic.
Metal parts like the pump impeller and valve stems corrode faster than plastic. You may not see the damage until the pump fails or the valve stops turning. By then, the repair bill is much higher than the cost of the right dispenser.
The right way to dispense chlorine tablets
Use a floating chlorine feeder or in-line tablet feeder instead. A floating feeder is a plastic cage that holds tablets and drifts around the pool. Water flows through it slowly and evenly, dissolving the tablet gradually and spreading the chlorine across the whole pool. You adjust how fast the tablet dissolves by opening or closing a dial on the feeder.
An in-line feeder mounts on the return line after the filter. Water from the pump flows through the feeder, dissolving the tablet, and then back into the pool. This method gives you the most control over chlorine levels because the feeder is always working when the pump runs. In-line feeders cost more to install but are worth it if you have a larger pool or want precise dosing.
For smaller pools or above-ground pools, a floating feeder is simpler and cheaper. Either way, the tablet is exposed to moving water, not sitting in a dead zone, so it dissolves evenly and the chlorine spreads throughout the pool instead of concentrating in one spot.
What to do if you have already put tablets in your skimmer
Remove the tablets right away. Turn off the pump and let the skimmer drain. Inspect the inside of the skimmer basket and housing for white spots, cracks, or pitting. If you see damage, the plastic is already compromised and will fail sooner or later.
Check the pump housing and the clear part of the filter (if your filter has one) for the same signs. If the damage is minor—a few small spots—you can keep running the pool but plan to replace the skimmer or pump within the next season. If the cracks are large or the damage is widespread, stop using the pool and call a pool technician. Running the pump with a cracked housing or damaged seal can cause the pump to fail suddenly and leave you without circulation.
Drain and refill the skimmer basket with fresh water to rinse out any tablet residue. Then switch to a floating feeder or in-line feeder for all future chlorine dosing.
Why the skimmer is not designed for tablets
A skimmer's job is to pull water from the surface and catch leaves, bugs, and debris before they sink. The basket inside is a strainer, not a chemical reactor. The plastic used in skimmers is chosen for durability in normal pool water—pH around 7.2 to 7.6 and chlorine levels around 1 to 3 parts per million. A chlorine tablet dissolving in the skimmer creates a pH of 2 or lower and chlorine levels of 100+ ppm in that small space. The plastic cannot handle that.
The skimmer also has a weir door—a flapper that lets water in but keeps debris out. Chlorine acid corrodes the hinge and the rubber seal on the weir door, so it stops closing properly. Once the weir door fails, the skimmer cannot skim the surface anymore, and leaves and bugs end up in your filter instead.
Chlorine tablet alternatives for different pool setups
If you have an above-ground pool with no built-in skimmer, a floating feeder is your best option. It is inexpensive, straightforward to use, and works in any pool. You just drop it in and adjust the dial.
If you have a concrete in-ground pool with a skimmer and pump, an in-line feeder is the most reliable choice. It mounts between the filter and the return line, so the tablet dissolves as water flows back into the pool. You do not have to fish a floating feeder out of the water, and you have better control over dosing.
Some pool owners use liquid chlorine instead of tablets. Liquid chlorine dissolves when ready and does not require a feeder, but it is heavier to handle and degrades faster in sunlight. Chlorine powder (calcium hypochlorite) also works and dissolves quickly, but you have to mix it in a bucket before adding it to the pool. Tablets are convenient because they dissolve slowly and last longer, but only if you use the right dispenser.
Frequently Asked Questions
Can I put chlorine tablets in the skimmer just for a few days?
No. Damage starts when ready as the tablet begins to dissolve. Even a few days of exposure will corrode the skimmer plastic and pump seals. Use a floating feeder instead, which takes the same amount of time to set up and does not damage anything.
What if my skimmer already has white spots but no cracks?
The white spots are the beginning of corrosion. The plastic is weakening. Remove the tablets, switch to a floating feeder, and plan to replace the skimmer within the next year. Do not wait for cracks to appear, because once they do, the skimmer will fail during the season.
Will a floating feeder work in a windy pool area?
Yes, but you may have to retrieve it if wind pushes it to the edge. Some pool owners tie a rope to the feeder so they can pull it back to the center. Alternatively, an in-line feeder solves this problem because it stays mounted on the return line and does not float.
How often do I need to refill a floating feeder?
That depends on your pool size, how much sun it gets, and how many people use it. Most floating feeders hold enough tablets for one to two weeks. Check the feeder every few days and add a new tablet when the old one is mostly dissolved.
Can I use chlorine tablets in a saltwater pool?
No. Saltwater pools use a salt chlorine generator (salt cell) to make chlorine from salt. Adding tablets introduces too much chlorine and can damage the salt cell and the pool equipment. Stick with the salt generator only.