Pool was fine until we covered it-HELP!!!!!

Hi! My pool is a vinyl lined 16 x 32 with no steps. Liner is 7 years old and in excellent condition. I started noticing last year when we covered the pool for winter that I had a little bit more of a water loss than previous years-Nothing MAJOR, but just something I noticed and mentioned to my husband. I kept a close eye on it and added water as I thought it needed it. No problem...This summer, water levels were fine and no major losses of water, other than evaporation. Well...here is the problem. My husband vacuumed, as he has done to this pool for the past 13 years and we covered it. Only then did I notice a HUGE amount of water missing.

In 20 days we lost about 9 inches of water and now it is going slower than before. Almost to the return jets now-and that is where I think the problem is... Last year the O-ringie things that you use with the plugs for the return jets were kinda crumbly, but my husband used them anyway-and this year, they were horrible so he threw them away and used nothing..THAT is the only thing we did differently that years past...So could that possibly be the problem? OR could it be the covers for the return jets? The pool was built in 93 so I am sure that those items are old and maybe slightly cracked? Or am I looking in the wrong direction for this water loss problem?

Husband is pretty sure he did not rip or poke a hole in liner when vacuuming, so I can't figure out where the problem lies. There are NO puddles or wet/soft spots in the yard, but not sure how that would be where the pool was built. It slants down on all sides with apple and pear trees on the backside/deep end, pump near shallow end and sloping all other sides too. Kinda up on a little knoll. Oh and there isn't any water in the only drain pipe that we can see.
Any thoughts on this would be greatly appreciated.

Finding leaks in a pool is a difficult task, at best. I'm surprised that you're not seeing evidence of a leak, though, with that much water loss. The only thing I know to tell you is to just wait until the water stops dropping, then look around the waterline and see what you can find--The leak is going to be just above the waterline when the level stops dropping.

Welcome to the forum!

Thanks for the welcome! I am sure I will be using this site in the months to come! The pool has stopped leaking and is just at the returns. We have not uncovered yet, but will this weekend with nice weather and husband off from work. At least it has stopped and we are able to reach down the sides to repair/replace whatever we find, instead of having to get in the water! Thanks again and I will update as we find our problem!

Good luck--hope it's something easy! :)

I didn't wait for hubby to get off this weekend, but chose to uncover myself and find that cause of my worry! I have went over the entire pool surface just above the water line and I have found NO holes, rips, tears, or even a rough spot. NOTHING! Even the seam looks as good as it did the day the pool was installed! The water level has stopped at the returns, so I am thinking it might be them, but I did a dye test and found nothing sucking the red out of the water! Nothing again! The only thing left is the returns. Do you think I should replace the face plates on those things (they do look a bit ancient, never been changed that I know of) and replace the winter plugs with the o-rings? Any thoughts, ideas or help would be greatly appreciated!