Given that it's such a new tank, any chance the tank temps have gone above 80-85 for a few hours?
Are you also dusting w/ a multivitamin supp., or just calcium?
Tony could be right as well, I'd be leery of putting 5 frogs in a 20G... even "good group frogs" like vents. Vittatus and some mantella species are pretty much the only frogs I'd be comfortable doing that with.
If you're going to keep the last 4 in there, make sure you have at least one brom or comparable hide for each frog.... and extras never hurt. Vents will often share broms, but if they get into a tiff each frog should have somewhere to retreat.
I guess the most obvious question is, have you had fecals done? With three down out of 7, you've got to wonder if they might have something.
Are you also dusting w/ a multivitamin supp., or just calcium?
Tony could be right as well, I'd be leery of putting 5 frogs in a 20G... even "good group frogs" like vents. Vittatus and some mantella species are pretty much the only frogs I'd be comfortable doing that with.
If you're going to keep the last 4 in there, make sure you have at least one brom or comparable hide for each frog.... and extras never hurt. Vents will often share broms, but if they get into a tiff each frog should have somewhere to retreat.
I guess the most obvious question is, have you had fecals done? With three down out of 7, you've got to wonder if they might have something.