Hi i got a 900L tank and i got around 20 fish everyday since 3 days ago 1 or 2 fish have died and it was my king kong . in my tank i have 2 electric yellows , 2 oscar,2 red parrot , 3 flower horns, 2 king kong and so on. i get a reading of 7.2 PH. ive added 200 ml of water ager , 200 ml of magic...