definately do not want to glue it. if i get bored of it i want to be able to remove it. and i know duct tape wont work
but the marble idea is a thought other than itchanges the hight of the structure which will cause me a problem with the over flow it would have to be thinner than 1/4 inch. i may try notching a portion behind it out. i have a spare koralia #1 magnet/suction cup i can try to attach to the structure. ill have toremove it and dry it out and see.
very good ideas tho thank you i wasnt thinking marble, any other ides are welcomed.