I have a 10 gallon stand...and the bottom holds a 5 gal tank as well. Now I can only find the 5 1/2 gal tanks at all my local fish stores. I am assuming it will hold that, there can't be that much difference is there??
And I feel silly...but when u say cycle the water-you mean with a filter set up right? I saw a undergravel one for like $10 would that be okay. I personally dont like them, but I would think they would be okay for bettas?