Originally Posted by Nicknack
*species. There aren't any 'breeds' of dart frogs, thankfully.
I agree with PMB's concerns. The lighting intensity issue would be easy to troubleshoot -- temporarily put something translucent under your current lighting, or raise the fixture. If your plants have doubled in size in one month, it sounds like enough light to make frogs very uncomfortable.
Another issue might be the spectrum of that lamp --it is blue-shifted, and claims to emit a lot of UVA. Darts do avoid UV (UVB? UVA? I don't know for certain), and could be hiding more for that reason.
Even under optimal conditions, amazonica should be expected to be more shy than not.