I only have five, one 60, two 80's, a 100, and my 244 which has satisfied my in house MTS. What I want next is a pond under a gazebo 12'X12' in the back yard.
I bet these tank occupy good amount of your time. Who needs TV when you have MTS.
Pond in the back yeard, Huh?
At least you can jump in during summer to swim with fish as I have. Well least waist high.
I had built 12 ' x 18' x 2' indoor pond using either 5 x 5 or 8 x 8 treated lumber and 1" dowels to hold lumber stacked at each corner (required core drilling and lots pounding to drive the dowels..
It looked like Ranch fence from outside and but lined with plywood and pond liner inside. One corner of the pond i build platform to build DIY water fall using cement mix and lathe with epoxy coating. My original plan was to somehow incorporate enclosure to stock amphibians on this water fall and platform which I could not complete but end up installing water mill which was also beautiful. Added diy plant box at the perimeter of the 4 x 4 frame where I can dump some pond water which was a great ferlizer.
Good Luck with new project(s).