Freshwater angel laying on side

[fuzzysocks]

The short: one of my angels is laying on his side and barely moving. Appeared healthy until less than an hour ago.

The long: I had a mated pair of angels in a 30 gallon tank. They laid eggs on Friday night. This morning I noticed that the female was bullying the male, resulting in torn fins and a few missing scales. The bullying was pretty bad by this afternoon, so I put the male into a 55 gallon (after acclimating it) with 2 other adult angels. He looked alright for a couple of hours. I looked over ten minutes ago and saw the male on his side at the bottom of the tank, barely moving. All other fish in both tanks appear to be quite healthy.

I still can't see anything visibly wrong with the fish, beyond the torn fins. No tail clamping, red or white spots, elevated respiration etc. Any ideas?

[onefishtwofish]

could be stressed from the beating and then more stressed from being moved. water perimeters?