I was wondering if I could get some feedback from some fellow ponders.
I have always used the old 'Biobox' method in smaller scale ponds (up to about 8 x 8) comprised of the plastic box with the holes punched in it and a main exit hole for the tubing that leads to outflow, packed with filter material and bioballs.

I want to do a much SMALLER SCALE version to place into a 75 gallon terrarium/vivarium style set up (that will house no animals, just plants, but not be totally enclosed like a terrarium)

I was thinking of using one of those disposable 'take and heat' Glad containers for the box, and a small pump that I want to split the tubing to have an 'octopus' style multi-outflow to form a trickle wall in a few places.

The thing is I don't want to cement everything in with Great Stuff foam because I may change the set up later. Do you think a biobox is feasible? There would be a false bottom to the set up so that the water reservoir is separated from planting media. Most people just stuck the filter directly to the side of the tank with suction cups.

Most of us around here have to rig our aqariums with various supplies from the hardware store. There arent any celebrated pond services here. And the pond store is an hour away in a good day!

I think you idea I'd feasible because you know how a biobox filtration system works. But for a 75 gallon tank if you dont want to make your own, there are available biological filtration systems made for fish tanks of that size. The tubing you can get creative with. They may hang on the side or concealed in its own box within a tank both non permanent. I'm not sure what your rank set up would be like, but these ideas first came to mind.