Back at it.

[Delphinus]

They are very touchy. And very sensitive to water level fluctuations.

I run mine in a sump, that way I don't have to worry about overflows. I can't imagine trying to run one of these as an actual hang-on like it's intended... I'd have had far too many floods on the floor.

I think it's a judgment call with the angels. I have two small flame angels in a 20g. They will eventually outgrow it, but until that day, or until they start showing aggression with one another (I'm kind of hoping they'll form a pair, but who knows), they seem to be fine for the time being. They are really small though, like 2" in size, that's a big factor.