How much water loss is considered "normal"?


Well-known member
May 29, 2017
Worcester, MA
Hi folks. Pool newbie here. Just finally got FC issue taken care of thanks to the folks here. SLAM is a great process.

Anyway, I was away this week for work but my wife and kids were home and used the pool.

On Tuesday I took note of the water level which was exactly level with the tile grout line in my pool.

I returned home today on Friday and it seems we have lost about 1" of water over the past 3 days. The pool was used each day by 4-6 kids for 2-3 hours. It was also VERY sunny.

Is this amount of loss considered "normal" due to either splash out and/or evaporation? Or is there a leak?

My main drain is partially blocked due to chunks of plaster inside from when the previous owner resurfaced the pool a few year back. I've been trying to get it out and worry I somehow broke the main drain line.



LifeTime Supporter
Aug 19, 2014
Pacific NW
That sounds about right.

It really goes quick when the water is warm.

What is the water temp?

Do you cover the pool daily?

I cover mine and keep it at 84 degrees most of the time.
I lost 1/2 inch of water this week from sun-thur


Well-known member
Jun 11, 2016
Boston, MA
Just FYI. I am in boston area too. For this past week, it is hot during the day, I lost about 5/8"-3/4" in 4 days with kids in the pool 1-2 hours a day.


TFP Guide
Jun 5, 2012
Central PA
If you're really not sure, you can do the bucket test to check for water loss. You place a bucket of water, place it on the steps, with the water level the same as the pool. In 24 hours (I think that's the recommended time) you check to see if there is a difference in the water levels between the two.

I can lose a half inch of water when my son has friends over and they do cannon balls.