Is there any reason why a canister filter type design wouldnt work? I read somewhere how the algae shouldnt be submerged in the water but rather needs the water flowing over it.If so what is the reason for this? I had made this design which I was thinking of using. It is highly energy efficient(not space efficient) and can also be sealed. I was also thinking of several other designs based on wet/dry trickle fitlers.
I have attached a design. It can seal by gasket or simply overflow into the tank.