I have all my angels in hard tap water ph 7.6 have had them for over a year and lost only 1 ,I feed my a mixture of hbh 5 flake frenzy mixed with alot of spirilina.I use to lose angels all the time but found a good place to get them from .alot of wholesalers just crowds them up too much and by the time they reach the pet stores they are wat streesed.