Like a touch pond at long beach aquarium! Sweet. So external return pump I think reeflo dart gold I think is the "best" option. I still don't know what "rw" is but as far as lighting it's fish only right? You could use anything man. Like literally anything you like the look of, you're not viewing from the side so shimmer isn't a goal, blues don't matter so that kills all expensive led options. Any way you could direct natural light into the "tank"?