Floater or feeder: the same tablets, metered two different ways

The practice both of these replace

Putting tablets in the skimmer basket is common and it is the wrong answer. With the pump off, the skimmer and the pipework beyond it sit full of concentrated, acidic dissolved trichlor, which attacks metal parts and fittings. It also dumps a slug of chlorine into the pool when the pump restarts.

A floater or a feeder both solve that, by holding the tablets where the dissolution rate is controlled and the concentrate is diluted immediately.

What each one is

A floating dispenser is a vented plastic container that holds 3-inch tablets and drifts on the surface, with an adjustable base that sets how much water passes over them. Our floater roundup covers the models.

An off-line feeder is plumbed into the return line beside it rather than into it, holds 4.2 lb of tablets on the common above-ground unit, and meters the feed with a dial valve. It fits above-ground filter systems through a universal adapter kit and has a corrosion-resistant housing. Our feeder roundup has the detail.

The liner question

A floater can park itself against the wall or in a corner and sit there, holding a concentrated tablet against vinyl for hours. That is a genuine bleaching and weakening risk, and it is the main practical argument for a feeder on a vinyl pool — our liner guide covers what damages vinyl.

It is manageable: nudge the floater away from the wall when you pass, and take it out before a long absence. But it is a habit you have to keep, and a feeder removes the need for it entirely because the tablets are never in the pool.

What neither one fixes

Cyanuric acid. Trichlor tablets are stabilized, so every tablet either device dissolves adds CYA that only leaves by replacing water. That is the same regardless of how you meter them, and it is why our stabilizer guide matters more than the choice on this page.

If your CYA is already climbing, the answer is not a different dispenser — it is alternating with an unstabilized product, covered in our shock roundup, or diluting.

Who should buy which

Floater for a first season, a small pool, or anyone testing whether tablets suit their routine at all. It is cheap enough that being wrong costs nothing.

Feeder for a larger pool, a vinyl liner you want to protect, or a household that travels — capacity and a dial beat a floater you have to refill and reposition. Our vacation guide covers the week-away case.

Setting either one correctly

Both devices meter by exposing more or less of the tablet to moving water, and both are usually set wrong on day one — too open, which burns through tablets and spikes chlorine, or shut so far that nothing dissolves.

1. 1

   Start nearly closed

   Open the vent or the dial a quarter, run the pool for two days, then test. It is far easier to open up than to pull chlorine back out.
2. 2

   Test at the same time of day

   Chlorine readings move with sunlight and bather load. Comparing Tuesday morning with Saturday evening tells you nothing.
3. 3

   Adjust one step at a time

   One change, two days, one test. Chasing the reading with daily adjustments is how people end up dosing blind.
4. 4

   Keep the floater away from the wall

   Nudge it toward the middle when you pass, and take it out before you leave for a week.
5. 5

   Empty either one before you close the pool

   A feeder or floater left loaded over winter is concentrated tablet sitting against plastic for five months.

What goes wrong with each

Floaters get stuck. They park in a corner, behind a ladder, or against the skimmer where they starve the rest of the pool and over-chlorinate one spot. They also get picked up and put on the deck by children, at which point the pool has no sanitizer until someone notices.

Feeders fail differently: a dial left open after a shock, or a unit that is not drained before winter. They are plumbed, so a leak is a leak on your equipment pad rather than a nuisance in the water.

The stabilizer arithmetic neither solves

Trichlor tablets are about half stabilizer by the time you account for what dissolves, and cyanuric acid does not evaporate, break down or get filtered out. It accumulates until the only way down is replacing water, as our draining guide explains.

That is the real long-run cost of tablet chlorination in either device, and it is why our tablets against liquid comparison matters more over a few seasons than the choice between a floater and a feeder. Test cyanuric acid monthly rather than annually, and alternate with an unstabilized shock when it starts to climb.

Handling tablets safely

Trichlor tablets are an oxidizer and they are handled far too casually. CDC guidance on pool chemicals is to keep them in the original labeled container, store each product separately away from incompatible chemicals, and keep them below 95°F, dry and out of direct sun.

Three habits follow. Never mix products or reuse a scoop between them. Never stack a tablet bucket next to shock in a hot shed. And close the bucket properly, because trichlor gives off fumes in a confined space and a damp bucket is a genuine hazard rather than a theoretical one.

When you load either device, do it out of the pool, dry-handed, and put the lid back on the bucket before you walk away. Our storage guide covers what keeps over winter, and tablets stored sealed at a stable temperature keep well — published figures put trichlor at 98% of available chlorine after three years in those conditions.

The honest recommendation

Start with a floater. It costs less than the tablets it holds, it works, and if tablets turn out not to suit your routine you have lost nothing.

Move to a feeder when one of three things is true: the pool is big enough that a floater needs refilling more often than you will do it, you travel and need capacity, or you have found a bleached patch on the liner where the floater parks. Each of those is a specific reason rather than an upgrade for its own sake, which is how this site treats equipment generally.