Your pool filter is one of the most important parts of the circulation system.

It removes dirt, debris and other unwanted material from the water as the pump circulates it through the filter.

But a filter can only do its job properly when it is maintained.

A dirty or restricted filter can reduce water flow, interfere with circulation and contribute to problems such as cloudy water and algae.

So how do you know when your filter needs attention?

Start by Knowing Your Normal Filter Pressure

One of the best things you can do is learn what your filter pressure normally reads when the filter is clean.

That gives you a baseline.

As the filter collects dirt and debris, the pressure can rise and water flow can decrease.

Your pressure gauge may not be perfectly accurate, so don't become obsessed with the exact number. What matters is knowing what is normal for your particular system and recognizing a significant change.

What Can Cause Filter Pressure to Rise?

There are plenty of reasons a filter can become restricted.

For example:

• Dirt and debris

• Leaves and vegetation

• Pollen

• Algae

• Dead algae after treating a green pool

• Heavy environmental contamination

Florida pools can sometimes collect a surprising amount of material, particularly during periods of heavy pollen, storms or surrounding landscaping activity.

Your filter may need attention much more frequently during those periods.

What Happens If You Ignore a Dirty Filter?

As the filter becomes clogged, resistance increases.

Water flow can decrease.

And when circulation decreases, other pool problems can follow.

This is particularly important when you're already fighting algae.

Imagine treating a green pool and killing the algae, only to allow the dead algae to remain in the filter until circulation becomes restricted.

The reduced circulation can make it harder for the pool to recover.

A clean pool filter is part of maintaining good pool circulation.

Different Filters Need Different Cleaning Methods

There are three common types of pool filters:

Sand Filters

Sand filters are cleaned using a process called backwashing.

Water is directed through the filter in the opposite direction to normal filtration, carrying accumulated dirt and debris out through the waste line.

The exact procedure depends on the filter and valve configuration, so follow the manufacturer's instructions.

D.E. Filters

D.E. (diatomaceous earth) filters also use a backwashing process.

After backwashing, the appropriate amount of D.E. normally needs to be replaced so the filter can continue trapping fine particles.

The amount required depends on the specific filter.

Cartridge Filters

Cartridge filters are cleaned by removing the cartridge elements and washing the accumulated dirt from them.

Pay particular attention to the folds of the cartridge.

If material remains trapped deep inside the folds, water flow can remain restricted even though the filter looks cleaner from the outside.

Cartridges are also consumable components and eventually need replacement.

How Often Should a Pool Filter Be Cleaned?

There isn't one schedule that works for every pool.

Your original Monkey Rock experience was that monthly cleaning can be sufficient under some conditions, but some pools need attention considerably more often.

For example:

• A pool surrounded by trees

• Heavy pollen periods

• An algae bloom

• A pool that receives lots of debris

• A pool undergoing cleanup after a green-water problem

can all increase the amount of material being captured by the filter.

Rather than blindly following a calendar, watch the condition of your pool and your filter pressure.

What About a Green Pool?

A green pool can put an especially heavy load on the filter.

Once algae has been killed, the dead material has to go somewhere.

The filter is one of the places that material ends up.

That's why filter maintenance is an important part of recovering a green pool.

If the filter becomes heavily loaded and water flow drops, circulation can suffer — potentially making the recovery process take longer.

Don't Forget the Baskets

The filter isn't the only thing that needs attention.

Your skimmer basket and pump basket also collect debris.

Leaves, grass and other material can restrict water flow if the baskets become full.

Checking and emptying them regularly is a simple maintenance task that can help the circulation system operate properly.

A Word About Pressure Gauges

Pool filter pressure gauges aren't always perfectly accurate.

That's why we recommend becoming familiar with the normal reading for your pool when the filter is clean.

The change from your normal reading can be more useful than focusing on an exact number printed on the gauge.

If the pressure suddenly rises significantly, investigate the cause.

The Bottom Line

Your pool filter is not something you should simply clean once in a while because the calendar says it's time.

Learn how your system behaves when everything is clean and working properly.

Then watch for changes in:

• Filter pressure

• Water flow

• Water clarity

• Pump operation

• Pool debris

• Algae

• Overall circulation

A filter that is doing its job helps keep your pool water clean and your circulation system working properly.

And when your pool starts developing recurring algae, cloudy water or poor circulation, don't overlook the filter.

Need Help With Your Pool?

If you're unsure whether your filter is working properly, or you're dealing with recurring water-quality problems, Monkey Rock Pools can inspect the system and help identify the underlying problem.

Related Monkey Rock Pool Tips

• Why Does My Florida Pool Keep Turning Green? 5 Common Causes

• Why Won't My Pool Hold Chlorine?

• How Long Should My Florida Pool Pump Run?

• How To Fix Cloudy Pool Water

• How To Clean a Pool