I am new to this forum. I have a 19 foot above ground pool with a vinyl liner. I have no idea how old anything is because I inherited the pool 7 years ago when I brought my house. I've had issues with it but this year has probably been the worst. I now have a leak somewhere in the pool that began yesterday most likely due to my son using a metal pipe and pole vaulting while in the pool. Unfortunately, I can't see the leak because the water is green. The water is green because I had some issues mainting water pressure in the pool due to a bad head valve and from some debris that fell into the pool while removing the cover. Also the lateral in the filter cracked when I first opened the pool, so there is about 50lbs of sand on the pool floor. The water level dropped almost 4" overnight. I checked the hoses, filter, skimmer, etc. just to make sure the leak wasn't coming from anywhere else but the pool. I really can't afford to replace the liner this year, so if anyone has any suggestions I would appreciate it. I refilled the 4" lost and added some shock and algaecide to try to get the green out. Thanks.