"moved them into one of my old snake's cage that is
6'1/2 L x 4'1/2 H x 3' W"
That should be a good size for your two dragons, they will be really happy in there.
A good site to read up on general dragon care is:
http://www.icomm.ca/dragon/
There is also a link to a yahoo WaterDragon discussion list somewhere on that page.
The *other* fourms over at "queensnake.com" have an active waterdragon forum as well and can answer any additional questions you have.
(But, I have to point out, this is why they say research *before* you get a herp...waterdragons are a lot of work compared to most snakes)