I have a Intex 15ft by 4 ft deep pool.

It's the one with the metal poles. We had the same problem last year, so I got a bigger pump. Instead of the 1000 gallon per hour filter/pump, I upgraded to the 1500 gallon per hour pump. Well didn't help. I have put tons of shock in the pool, algecide, I have raised the PH and lowered the PH. (I have test strips). I have tried to vacuum the pool. EVERYTHING!! I've spend TOOOOO much money on chemicals and I don't know what else to do.

I'll shock it one day and the next I'll test the water and it says no free chlorine. HELP PLEASE!!!