Filling an Above-Ground Pool for the First Time: Step by Step

If you're working out how to fill an above ground pool for the first time, plan on two speeds. The first inch or so goes in slowly while you push liner wrinkles out toward the wall, and after that the water goes in as fast as you can get it. Before either, the pool has to be level and the base smooth, because once a pool an inch and a half out of level has 10,000 gallons in it, the only fix is to drain it and start again.

Check level and base before a drop of water

Walk the pool one last time with the wall up and the liner in.

Start with level. A common manufacturer spec is level within about an inch across the whole diameter. Check with a long straight board and a level across the bottom track in several directions, or with a string and line level from a center stake to each upright. A pool 2 inches out shows a slant at the waterline and loads one side of the wall harder, which can make the wall buckle on the low side.

Then check the base. No stones, roots or sharp edges should be under the sand or foam pad, since anything you can feel by hand can wear through the liner under 4 feet of water. The sand cove where floor meets wall should be smooth all the way around.

Next, look at the liner. Overlap liners can be adjusted over the wall as the water goes in, while beaded liners need the bead seated in the track before the first gallon. Vinyl is easier to work when it's warm, and several liner makers ask for about 70°F or warmer. The filling a pool in cold weather guide has more on timing.

Last, the equipment. Have the pump and filter plumbed, since the skimmer and return go in during the fill.

Common sizes: gallons, hose time and loads

Figures use 4 feet of water, the depth most gallon charts use for a 52-inch wall, with the standard formulas (round: diameter x diameter x depth x 5.9; oval: length x width x depth x 6.7). Hose time assumes a typical garden hose at 5 to 10 gallons a minute, and loads assume a 6,000 to 8,000-gallon tanker.

A 48-inch wall holds about 3.5 feet of water, which takes roughly an eighth off every figure, and the pool gallons chart has every wall height and size. The hose column is running time, and plenty of people shut the hose off overnight, so a 24 ft round is a weekend by hose and usually one day by truck. Most above-ground pools take 1 to 3 loads, and the quote gives the exact price.

Setting the liner in the first inch or two

This is the part people rush, and it decides whether the floor stays smooth for the life of the liner.

1. Put the hose end in the center of the floor with a sock over it or resting on a towel, so the stream doesn't dig into the sand, and open the tap about halfway.
2. At about half an inch of water, get in barefoot or use a soft push broom and work from the center out, pushing wrinkles toward the wall and into the cove. Stay just ahead of the water.
3. On an overlap liner, take the coping off one piece at a time as the water rises and adjust the wall, letting material in where the floor pulls tight and taking up slack where it's loose. Smooth floor wrinkles from inside the pool, not by hauling liner over the wall.
4. If you have a wet-dry vacuum, slide its hose through the skimmer opening in the wall, behind the liner, seal around it with tape, and run it while the pool fills, keeping the vacuum hose above the water. It pulls the liner flat and removes wrinkles your feet won't. Instructions vary on how long to run it, so follow yours.
5. Once 2 to 4 inches cover the floor, the water's weight holds the liner and remaining wrinkles will mostly stay. One manufacturer's manual warns against lifting and pulling the liner with more than 4 inches of water over a wrinkle.
6. Open the tap fully, or let the truck driver go to full flow.

The filling a pool with a new liner guide covers the same step for in-ground vinyl, where the vacuum trick is standard practice.

Hose over the top rail or tanker hose

By hose, the end rests on the floor for the liner stage, then gets tied to the top rail so it can't slip out onto the lawn. Run a second hose from a second spigot if you have one, and time a 5-gallon bucket to get your real flow: 30 seconds is 10 gallons a minute, 60 seconds is 5. On a private well, more hoses don't help, because the pump and the well's recovery rate set the limit. A day-long run can also strain the well, which is why many well owners have the water trucked in.

By tanker, the truck parks on the street or driveway and the driver runs a hose to the pool, over the top rail with the end resting inside. The first 300 feet of hose from the truck are included, a longer run adds a hose charge, shown in your quote. Tell us the pool is new so our hauler knows to start slowly while you set the liner. Each load usually unloads in well under an hour, so a one or two-load pool is often full the same day. The above-ground pool fill page covers access, hose distance and what the quote includes.

When to install the skimmer and return

Don't cut the liner for the skimmer or return before there's water in the pool. The water's weight stretches the liner against the wall, and liner makers warn that fittings installed too early can tear the liner away from the opening. Most say to wait until the water is about 3 inches below each opening.

The return usually goes in first because it sits lower. When the water is about 3 inches below the return opening, press the liner flat against the wall, fit the gaskets and faceplate through the liner and the wall opening, tighten the screws evenly, then cut the liner out inside the ring.

The skimmer is the same job higher up the wall. When the water is about 3 inches below the skimmer opening, fit the faceplate with the gaskets placed as your skimmer's instructions show, screw it down evenly in a star pattern, and cut the liner inside the frame, unless your manual says to cut first.

With a hose, the water rises slowly enough that you can just watch the level. With a tanker it rises much faster, so show the driver where the openings are and ask for the flow to stop about 3 inches below each one while you fit it.

Starting the pump and first chemicals

Stop at the middle of the skimmer opening, or a few inches below the top rail on a pool without a wall skimmer. Connect the hoses, prime the pump and run it continuously for the first 24 to 48 hours, checking every fitting and both faceplates for drips.

Then test and balance in order: total alkalinity, then pH, then calcium hardness, then stabilizer, then chlorine, one change at a time with circulation in between. The target ranges and their sources are in what to do after the fill. We deliver the water but don't do chemical start-ups, so the chemistry is yours to handle and this page stops at the handoff. For other pool types, the complete fill guide has the procedure.

Frequently asked questions

How level does an above-ground pool need to be?

Within about an inch across the whole pool is a common manufacturer figure, and closer is better. Measure across the bottom track in several directions before the liner goes in. Two inches out stresses the wall on the low side, and once the pool is full the only real fix is to drain it.

Should I fill a new above-ground pool all at once?

Mostly, yes. Set the liner slowly over the first inch or so, pause to fit the return and skimmer when the water is about 3 inches below each, and otherwise keep filling to the middle of the skimmer.

Can a water truck fill a brand-new above-ground pool?

Yes, and it suits the job. The driver can usually start slowly while you set the liner, then go to full flow, and many sizes take one or two loads, so a pool set up in the morning can be full that afternoon. Mention that the pool is new when you ask for a quote, and balance the water before anyone swims.

What if I see wrinkles after the pool is full?

Small floor wrinkles are cosmetic, and liner makers treat slight wrinkles as normal. Large folds, or wrinkles up the wall, trap dirt and wear faster, and fixing them usually means lowering the water below the wrinkle and resetting the liner on a warm day.

Many above-ground pools take one or two loads, and the bigger ones three. Tell us the size, the wall height and the ZIP, and a person sends one delivered price, usually within 1 to 2 business hours. Get your delivered price.