This spring, I noted a loss of 1"/24h within the first couple of weeks of opening (opened first weekend in May). This is with the pool completely covered with a solar blanket. I measured this loss rate with the pump running, and with the pump off, and also with the skimmer and returns plugged (there is no main drain, but I do have a light and steps). I take from this that the leak is happening somewhere within the pool walls. I did a close inspection of the liner and noted nothing. I did observe tiny bubbles coming from only one of the 2 returns when the pump is running.
The really bizarre thing is and this is my question, once the pool temperature approached & surpassed 80F, I have yet to observe a loss of water after 6 days! I'm wracking my brain trying to figure out how this is possible. My best theory is that the warmer water is causing whatever part is leaking to expand, and close off a crack or fissure, or maybe apply more pressure to a gasket?? Now I can't really have a diver come and search for the leak because it just isn't happening all of a sudden after 3 weeks of leaking.
Would really appreciate the forum's thoughts/opinions/ideas on why the leak would go away with warmer water.