as far as your rams go, i have never heard of rams actually killing another fish, though with the breeding they do become aggressive no where near as some other cichlids, i have a midas and convicts so aggression in my terms is missing fish or torn all to heck fish, How big was your plec, cuz they do seem to get the brunt of aggression being slow moving bottom fish, and the rams spawned on or rootwood, wich plecs like to eat wood. Now back to the point, the fry survival rate is very limited especially if this is the first time your rams has spawned, i have never had luck with them, they either eat the eggs themselves or eat the fry afterwards, nowhere near as good parents as midas or convicts(not currently breeding them at the moment). Your discus are good and hardy and can withstand anything that a little ram can dish, but your plec depending on the size might have gotten some ruff treatment, mine have in the past, though they are supposed to be tuff i don't really know crap about em. I would take the rams back to the lfs, sorry but the spawn prob wont make it anyways, and it seems to have stressed you out. If you want to keep them, I would take the eggs out to another tank, and raise them yourself, that seems to be the only way to keep em alive that i have seen anyways and would cool aggression, but leave the parents with the discus

My two Keyholes will quite happily chase off Cory's all day. But I've never seen them look twice at a Bristlenose.

Next time they spawn, I'll watch for that.