most canisters come with ball valves on intake and exhaust, as long as they are both under the water and everything is sealed up not to leak what is the problem?
where there is a will there is a way. It will work its just a matter of how much plumbing work needs to be ensure no leaks in the lines or in the tank.
technically, if he had the plumbing parts that go in the tank and overflow itself and plumbed his canister lines to fit into properly the bulkheads then it will be fine.
I dont know much but I own every style filter made right now and while having to retrofit things to work everything is fine all it takes is a few minutes of brain power and a few hours max of physical and mental energy.
Joe, you can run all the plumbing IN the tank that is supposed to be there, under the tank where the holes are, your bulkhead ends meaning what connects the tank plumbing to the canister plumbing will have either double female ends or if you get a bulkhead that has a female/male ends, you hit the garden section, get yourself some connectors to the thread to a hose so one end will match one end of your threads, then use a hose clamp to your hoses at that point and again at the valves and the canister lid if needed.
its a pretty simple retrofit to be completely honest.
That's not a planted tank. That's a jungle with glass around it- MFDROOKIE Circa 2011