A product which, IMO, everyone should be using: Sponge Power

[Delphinus]

Isn't that interesting! Not the whole "I think SP is fueling my hydroids" thing, but the "I think my Centropyge eats them". I totally missed the connection, but I've had a potter's angel for about 18 months now, and have noticed on a couple of occasions that I seem to have fewer hydroids. I always thought it might have been my CBB. Now I'm going to have to observe my potter's a little more, or try offering some hydroid covered rock to see if anyone picks at them.

Oh those darling little angels!