If you suspect that your pool has a leak, the first thing you should do is to locate the source of the leak. You can do this by performing a bucket test.
To perform a bucket test, you will need:
A large plastic bucket
Water
Marker or pen
Steps:
Fill the bucket with water to the top and mark the water level on the outside of the bucket.
Place the bucket on the first or second step of the pool with the water level at the same level as the pool water.
Turn off the pool's circulation and filtration system.
Wait 24 hours and check the water levels in both the bucket and the pool.
Compare the water levels in the bucket and the pool. If the water level in the pool has dropped more than the water level in the bucket, you have a leak.
Once you have confirmed that you have a leak, you can call a pool professional to repair the leak or try to fix it yourself if you are comfortable with pool maintenance.
It's important to act fast on suspected leaks as even a small leak can cause significant water loss and damage over time.
