7 Proven Ways to get an Above Ground Pool to Circulate Better

Above ground swimming pools can have issues with water circulation. This is because there are only a skimmer and one return line and they are right next to each other.

Most in-ground pools don’t have any circulation problems. Even the smaller ones have a skimmer, main drain, and at least three return lines going back to the pool in different areas.

You can improve the circulation in an above ground swimming pool by adding an extra return line, installing a main drain, positioning the return jet to create a whirlpool effect, or install an automatic cleaner.

WHY IS CIRCULATION IMPORTANT?

In order for swimming pool water to be and stay healthy, it must move and be filtered. Think of water in a still and shallow pond or a bucket of water left outside. In both cases, the water is just sitting there and not moving.

In this condition of stillness, it doesn’t take long for the water to get nasty with dirt and algae growth. Water is a great environment for life. And life will thrive in it when the water is very still, warm, and dirty.

Now, think of a fast-moving stream or river. Notice how the water is usually clear, clean, and healthy-looking. When the water is moving (especially rapidly), life has a harder time growing and living in it. Also, with a stream or river, the bottom and embankments are covered with an aggregate (rocks, smaller rocks, sand). The stream/river water gets filtered as it passes through the aggregate.

So, when water is moving, it’s oxygenating and particles in it are getting trapped by aggregates in the river bottom. These two things make for healthy water for us humans to interact with it. When water is stagnant, it doesn’t have much new oxygen, and debris that falls in it, stays. These two things make for dirty, slimy water which is not healthy for humans to interact with.

I am simplifying this but you get the point here. Water has to move and has to be filtered to be healthy for humans.

WHAT ARE “DEAD SPOTS”?

With using a natural stream as an example, have you ever been in one and noticed some areas or pockets where the water gathered and didn’t move much? And did you notice that in those spots, any rocks or earth around that pocket of water would be slimy or have growth of some kind?
In those pockets where the water could gather and stay is where life (algae) can easily grow, and so it does every time. These are called “dead spots”.

A swimming pool can have “dead spots” too. During my sixteen years of having a pool maintenance company in Orlando, I personally did weekly service on just under one hundred pools. These were mostly inground pools that had custom shapes. Many of these pools would have areas within them where, for one reason or another, the water wouldn’t circulate as well as the rest of the pool.

With these pools on my service route, every time I would get an algae bloom(usually yellow algae), the growth would always be in the areas where the water didn’t circulate as well. Sometimes, I would be able to turn the direction of a return jet or two allowing water to move towards these dead spots, and the algae would stop growing there.

POOR CIRCULATION VERSES NO CIRCULATION

Let’s say the pump motor in your pool goes bad and it takes a few days to get a new one. Your pool pump doesn’t run for those three days. This would be having NO circulation. You may notice that after even three days of the pool water not circulating, the pool starts looking pretty bad.

No circulation at all causes problems pretty quick, doesn’t it? What about only poor circulation?

Now let’s say that the pump basket in your pool pump broke some and allowed some leaves to get caught in your pump’s impeller (the thing that moves the water inside). You replaced the broken basket but didn’t notice that your pump is partially clogged and only pumping half the water through it that is normally does.

Your partially clogged pump is now not pumping as much water through it and not as fast as it normally does and this is resulting in your pool having poor circulation. The lesser water movement is causing a “dead spot” on the other side of the pool and not enough water is being filtered.

Over time, you notice that the pool gets a little dirtier, uses a little more chlorine, and gets mustard algae blooms more often, but that’s it. You may just think the small differences are from a season change with the weather or that the pool is just a little older and becoming more problematic. So you just live with it.

This is the big difference between poor circulation and no circulation. With no circulation, a pool owner has to make changes. People may just live with only poor circulation.

SOME ABOVE GROUND POOL STEPS CAUSE DEAD SPOTS

Pool steps for an above ground pool are nicer and more sturdy than just a ladder. But they do take up more space and can trap water behind them. Step manufacturers try to prevent dead spots by designing slats and openings along the sides to allow water to flow between the back of the steps and the pool’s wall.

But some will just trap water and cause a circulation dead spot. Usually, this will only cause some local algae growth behind the steps and that’s about it. For some though, it can cause more “global” issues as too much algae growth in one spot can promote more growth elsewhere.

If you think your pool steps are causing algae growth throughout the pool at times, the only thing you can do is try to move the steps an inch or two away from the pool’s wall. You can’t move them too far from the wall for the obvious reason that the steps will then be too far to be safely usable, but a little may help a lot with getting water to circulate behind them.

7 THINGS YOU CAN DO TO MAKE YOUR ABOVE GROUND POOL CIRCULATE BETTER

This list is in the order of cheapest and easiest to most expensive and harder to do.

Use the pool more

Every time someone gets into a pool and moves around, the water is circulating. This sounds simple and may seem stupid, but more activity in the pool is very effective at improving circulation.

During my pool maintenance years, I noticed that pools that got more swim action had fewer problems associated with poor circulation.

Turn the return jet parallel with the wall

This is especially effective with round-shaped above ground pools. Turning the return jet to send the water back to the pool(from the filter) parallel with the pool’s wall will create a whirlpool effect and take away any dead spots.

Bonus: You can unscrew the return jet on the inside of the pool and replace it with a PVC fitting which is a 1.5” 90° elbow with a male thread to slip. You can get this fitting at most hardware stores.

Run the pool pump longer

Sometimes People either aren’t running their pump long enough or their pump and filter are undersized. Most pool pumps will only need to run for eight hours every day over the hottest months. Some will need to run longer though to achieve the correct amount of circulation.

This is especially true for the cheaper Intex/Coleman type above grounds. The equipment that comes with them is very poor and needs to run longer.

Use an auto-cleaner

Automatic pool cleaners for above ground pools aren’t great, but they do help with circulation, a lot. This is because they move all around the pool and suck up water and send it back to be filtered.

These auto cleaners usually start acting up after a year or so and will not move around as much. It is still beneficial in terms of circulation though to keep using it even if it’s not picking up much.

The more expensive robot cleaners are also somewhat helpful with pool circulation, but not nearly as much as the kind that connects to the skimmer.

Add a return jet

As mentioned earlier, above-ground swimming pools only come with one return jet. This means that the filtered water only goes back to the pool in one place.

Adding another return can help a lot with circulation, but only really if the return is set much farther away from the original one. Most will add a return jet just a foot or two away from the factory one. This may be good in that it can cause better flow from the pump (if plumbed properly), but will only marginally help with the overall circulation of the pool.

Upgrade to a better pump and filter

Thirty years ago, most above ground pools came with crappy undersized sand type filters and cheesy pumps(I know because I was there). Today, most metal walled above ground pools come with a pretty good pump/filter package, but not all.

If you have a soft-sided Intex type pool, chances are upgrading to bigger and better equipment is needed. If your equipment is old or has never worked well, upgrading to something good will help a whole lot with circulation.

Add a main drain

I saved the best for last. Adding a bottom center main drain to an above ground pool may be somewhat difficult and/or expensive for what you have, but it’s the best thing you can do for pool circulation.

The biggest opposition pool owners have with getting a main drain is that it may leak. While it’s true that, if not installed properly, a main drain will leak, it’s not at all common.

With a main drain, you are now pulling unfiltered water from the bottom of the pool and at the top (from the existing skimmer). This will ensure very good circulation.

Bonus: When installing a main drain in an oval above ground pool, install it at the center of the radius (pools round end) opposite of where the skimmer/return jet is. It’s better for the drain to be at the other end of the pool bottom.

Changing the liner in your pool that already has a main drain? Don’t eliminate it. Keep it and make sure it doesn’t leak.