The dimensions are 24 1/4L x 12 1/2W x 16 3/4H ... not sure what a 10 gallon is off hand.
As for the pots, these are from a single piece of cork round and I ensure the hole through the center of it is big enough to accept plants before I buy it.
When I put these in I either silicone to the glass or I shove it into the foam right after I apply the foam and then adust angle while its curing. I cut out the excess foam inside to make room for soil and the plant after it cures.
Once wet and humid in the viv, the wood should stay pretty wet looking. 1st time using this wood so we'll see.