I had an idea for a behind tank refugium/filter thing

Surskit · Mar 15, 2022

Hey! I was thinking of setting up some kind of hang on back refugium for my tank, which there are plenty of diy tutorials for, but every way I had looked at it I realized it was gonna get in the way of my filter, so I was wondering if this would work. I would get a food/aquarium safe plastic container that's about the length of my aquarium, while being thin enough to fit behind it. I would then have it pump in water from the tank on the right with some sort of pump, and the right 3/4ths or so would have a light directly on it and be filled with macroalgae. Then I'd have a sponge to keep the macroalgae stuck in its area. And then I would fill the other section with filter media (something like those ceramic rings or maybe some activated carbon, or a mix of the two). Then I'd have another sponge near the back, protecting another pump that would pump water back into the tank. Apologies if my description wasn't great, I was just wondering if this would work.

EeyoreIsMySpiritAnimal · Mar 15, 2022

You will probably have difficulty getting water through the sponges without overflowing the first section. Sounds more like you're designing a sump than a fuge. What size tank do you have? What kind of filter?

MaxTremors · Mar 15, 2022

Surskit said:
Hey! I was thinking of setting up some kind of hang on back refugium for my tank, which there are plenty of diy tutorials for, but every way I had looked at it I realized it was gonna get in the way of my filter, so I was wondering if this would work. I would get a food/aquarium safe plastic container that's about the length of my aquarium, while being thin enough to fit behind it. I would then have it pump in water from the tank on the right with some sort of pump, and the right 3/4ths or so would have a light directly on it and be filled with macroalgae. Then I'd have a sponge to keep the macroalgae stuck in its area. And then I would fill the other section with filter media (something like those ceramic rings or maybe some activated carbon, or a mix of the two). Then I'd have another sponge near the back, protecting another pump that would pump water back into the tank. Apologies if my description wasn't great, I was just wondering if this would work.

You don’t want to pump water in and then pump water back, you want to rely on gravity for the return (overflowing back into the tank), using two pumps, even if they are identical, one will eventually pump faster than the other and either overflow or empty the container. I would recommend just buying a HOB refugium, I have the Fijicube one and it is excellent.