Loss Of Water During Backwash

by Pam
(NSW Australia)

Our pool just decided to do a back wash on its on this morning. Looked out and the water was at an alarmingly low point in the pool.


Thanks for the question Pam

When you backwash the filter you're going to lose water. This is normal as the dirt from the filter is being expelled from the filter. You should only backwash either for 2 minutes or so, or until the water runs clear out of the backwash hose.

Anymore than that and you'll lose too much water and possibly sand, if you have a sand filter. With a normal backwash you'll lose about 200 gallons, or about 600 litres.

The best remedy is to reduce the backwash time to 2 minutes or until the water runs clear. If you backwash too long, simply top the pool off with water, 1/3 - 1/2 up from the skimmer.

Hope this helps and good luck with you pool.


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Sand Filter W/ Good Water Flow In Recirculate But Almost None In Filter


I have a 24' above ground pool that is a light green murky color. It's a new pool w/ new sand filter and salt system.

When we just recirculate the water there is great water flow.

If we turn it to filter there is little to none.

Help please!

We did shock and tested the water the next day and all was normal except the pH which is high.

Thanks for the question

First, I'd like to have your complete chemicals readings:


CYA (cyanuric acid/stabilizer)



Calcium Hardness

Metals (iron and copper)

Total Dissolved Solids

It makes troubleshooting much easier and the process of clearing up your pool will go much faster.

You can get this done at your local pool store.

Without these numbers I'm just guessing at what the problem is with your green water.

Next is the sand filter.

These are some things to check:

1. Make sure there's enough sand in the filter and it's at the right level.

This is called "freeboard" which is the top of the sand to the top of the filter. Your filter manufacturer should have that information.

2. Using Baquacil and/or similar products can "gum" up your sand

3. The pool motor impeller is not gunked up with debris

4. Pump basket and skimmers are clean

5. Back wash the filter

Hope this helps and have a great Summer.


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