I tried sending something earlier and do not know if it went through. This is all new to me. But I had bought a house that had a pool that had sat for 3 years uncovered and unused. It was a fright. It is an above ground, vinyl liner with a bottom drain and pipes under the ground. I knew nothing about it let alone how to even get the filter going. I had a pool company come and they called it opening the pool. They got the filter going dumped 10 gallons of chlorine in it and left. Well I was excited to see it turning a little blue compared to green and that the filter worked.Well that was May 31st and today was the first time I had seen the bottom drain and the design on the bottom. Definitely thanks to your site and not the pool supply places. They never let me know anything about alkalinity (which was off the wall) or cyanuric acid (which I had none). Instead they just keep selling me chlorine and more chlorine which would just disappear. I still have to get the alkalinity down. This morning it was still 225 and I added more Muriatic Acid. I also may have to add more stabilizer yet but making progress. ? So thank you soooo much for your site. Phid