So we bought a house in December, and there is an above ground pool (~9000 gallons, 21ft across, round) in the back yard. It was blue when we uncovered it, but we had trouble with the pump and filter hoses leaking and it was green by the time we got new hoses that didn't leak.

We added shock, algecide and clarifier from Walmart and got it blue and sort of clear eventually, but the chlorine always went back to 0 after a day. The pool store sold us acid to make the chlorine last longer, they said it is destroyed quickly in the Texas sun. We put a gallon of the acid in and the pool got really crystal clear but the chlorine still wouldn't stay after a day and the ph got wonky. We haven't really been able to swim in it all summer, and after going on vacation it is now swamp green again. Super frustrating! We are ready to try round 2, but I want to make sure that I am putting in the right things in the right order.

Right now it is circulating with the pump and filter, but super green and nasty. I haven't put any chemicals in yet. What should I do first to get this under control? Thanks so much for any help, everything I've read online has been contradictory and confusing so far, so I could really use some solid advice! Thanks!