Hi everyone. Im not new here but this is my first post. We have inground liner pool - liner was replaced 5 years ago. Last year we suspected a leak but it was not much.
We have micro mesh winter cover but it is not sealed any good on sides, so to prevent dirt getting under we put large tarp over it (bad idea, never do it at home). We removed upper tarp about a month ago, so no top water was getting into the pool during winter months.
After opening the cover last week we discovered 3 feet of water drop and strange dark spot in the deeper part of the pool. Never had anything like this before. It is dark green kind of glued to the floor. Brush doesn't help to get it off.
Pool guys advised to try to put some vitamin C tablets - put a handful, nothing happened.
Attaching picture.
Any idea what it is and what can be done?
We have micro mesh winter cover but it is not sealed any good on sides, so to prevent dirt getting under we put large tarp over it (bad idea, never do it at home). We removed upper tarp about a month ago, so no top water was getting into the pool during winter months.
After opening the cover last week we discovered 3 feet of water drop and strange dark spot in the deeper part of the pool. Never had anything like this before. It is dark green kind of glued to the floor. Brush doesn't help to get it off.
Pool guys advised to try to put some vitamin C tablets - put a handful, nothing happened.
Attaching picture.
Any idea what it is and what can be done?
