Hey Bill - looks like your off to a great start, I'm so excited to see you starting on thins! I have one suggestion that would make filtration easier - how about a canister filter - drill glass for bulk heads and you can slip the filer intake /outflow through them. I have a 37g paludarium I am just finishing up the back ground on and took the plunge and drill the tank -After much debating and playing around with pumps, I left enough room for a small internal filter and my arm to fit down the back corner (about 4x5). The intake is below the water line on mine and the outflow about 7 inches about the water line with locline coming out the front on one corner and the opposite end of the tank has a small screened section (creating a circular flow across the front of the tank. I put the outflow above the water line to be able to unscrew the bulk head in the event I even need to clean it. Since the area is so small there would be no way to unscrew it from the bulk head from the inside, if the makes sense? I also have a small internal pump and hooked up a 6 port manifold to it and ran drip line to 4 spots where the water will flow down one side of the tank. I added drip flow regulators to each line and can adjust the drip to a flow and back. Anyway, just a thought
Looking forward to seeing your updates!