I did something like that with my 75. It wasn't very hard or expensive, it just took some time and effort.
The best solution I could come up with was an open-top tank. I got rid of my old hood and build a frame that fit on top of may tank, about 4" above the top of the tank, and another 2" below. It sits on the lip the same way a normal hood would.
For the "dry land" area, I built a background for my tank out of styrofoam on plywood, carved it to look like stone, and covered it in cement. It only stick out from the back of the tank about 2" most of the way up, but then at the top it overhangs like a shelf about 2/3 of the way over the tank. Just be creative to make it look like real rocks. I worked in some waterfalls and little pools, and rigged the return of my power filter through them.
This way, you can put some houseplants (pothos, philodendrons, bromeliads) in the top, with their roots in the water. They grow faster than water plants, and pull out alot more nitrates too.
Any questions, send me a PM.
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