According to my friendly neighborhood Petco fish lady they are going to be having a tank sale at the end of the month, from what I gather it is one of their 1$ a gallon deals, so my question is this, I am planning ( hoping if I don't get there early enough ) to grab a 20g long tank and was wondering is this going to be large enough planted for a trio of leucs or would something like Dendrobates auratus or tinc do better in one of these ? Would really like to get 2 Phyllobates terribilis "mint" but not sure if this tank would be suitable.

Any suggestions on which of those would be better suited for that size tank.

This is going to be a rather long time building as I have to do so on a strict budget so have to purchase it a little bit by bit with the frogs being the last thing to get while the tank grows in.