Greetings. I bought a house with an inground pool in 2012. Since then I’ve learned a lot but not so much that I think I know anything. It seems to be a different problem every year and each year I feel a great sense of accomplishment when I manage to solve it. I have a 15000 gallon 20’ octagon shaped pool. I am finding this forum today because I realized my biggest fear this morning upon removing the cover. All but 12 inches of water was gone.