I have heard that ADF's do best with very little to no current. My 125g has an FX5 and a CF-500UV so there is a bit of current between the two. Would that be an issue for these little guys?
You sure you don't mean the ACF's. Just wondering. ADF's look like their on the brink of dying everytime I see them. Always finicky and clumsy, I agree with Vicious. I doubt they could easily go up to that height to breathe without problems.
When I keep adf's. I use a little tiny shallow tank. If you can find a way to make a platform, I used a plastic leaf glued to the side of the tank or a piece of shale, about 1/2" below the surface they will make great use of it. Or a floating island. Like some floating plastic plants or cork bark