I would try to diffuse the current as much as possible, or simply unplug the pump and let the water sit. These dart frogs prefer to deposit tads in a small pool(maybe the brom, or stick some angled, large film canisters elevated on the tank wall), rather than in a stream type flowing water enviro. So they shouldn't even try to deposit the tads in there.... In the end, I would rather be safe than sorry!

JBear