Matten…ish AIO

[DeepDiver]

It has been a while since I have been on the forums. I set up and ran a 75g fish only tank with a Fuji Cube insert. It ran great with a dozen fish, anemone, cleaner shrimp, dragons breath and a cleaner crew.

I had to move a couple of times and currently have a pair of clowns in a 29g, very basic but stable setup. I am ready to move up to a larger tank, I have a 49g (36x24x12 outside) used tank. I want to make an internal filter based on the Matten filter concept. Rather than a weir and three chambers like a Fiji setup, or an open filter sponge as the ‘wall’, I would drill multiple holes for flow at all levels and to retain the sponge. The pump will adjust from 75-320gph, to give me up to 5x turnover with the ability to adjust down to maintain the ‘sumo’ water level.

The sketch is not to scale on the height.

Does this seem viable? Any concerns or adjustments?

 

[Besieged]

It has been a while since I have been on the forums. I set up and ran a 75g fish only tank with a Fuji Cube insert. It ran great with a dozen fish, anemone, cleaner shrimp, dragons breath and a cleaner crew.

I had to move a couple of times and currently have a pair of clowns in a 29g, very basic but stable setup. I am ready to move up to a larger tank, I have a 49g (36x24x12 outside) used tank. I want to make an internal filter based on the Matten filter concept. Rather than a weir and three chambers like a Fiji setup, or an open filter sponge as the ‘wall’, I would drill multiple holes for flow at all levels and to retain the sponge. The pump will adjust from 75-320gph, to give me up to 5x turnover with the ability to adjust down to maintain the ‘sumo’ water level.

The sketch is not to scale on the height.

Does this seem viable? Any concerns or adjustments?

This isn't quite a Matten filter in the usual sense - it's more like a hybrid between an internal sump and a sponge wall filter. That said, I think you'll run into some flow issues with this design.

Right now, water is going to take the path of least resistance through the sponge, which means you’ll probably end up with uneven flow, dead spots, and reduced filtration efficiency. A proper Matten-style setup typically has a divider or weir behind the sponge to create a gap and ensure water is pulled evenly across the whole surface instead of just one area. Otherwise, most of your filtration will happen near the holes, while the rest of the sponge barely sees any flow.

If you're truly set on this general design, you might want to:

• Add a baffle or divider behind the sponge to force even flow, either from the bottom up to the top, or from the top (like a typical AIO overflow) to the bottom.
• Position the holes lower to prevent all the draw from happening near the top.
• Consider using slots instead of drilled holes to further encourage uniform pull across the entire sponge. The exterior "wall" should be far more empty space than anything, and is really only serving to retain the sponge. The more of the sponge's surface exposed directly to water, the better.

Right now, it looks like water will just shortcut through the easiest route, which kind of defeats the purpose of using a sponge wall as a filter. If you tweak the flow path a bit, though, this could work well for what you’re going for.

 

[DeepDiver]

Ok, thanks. Would egg crate instead of the drilled holes make more sense?

If I’m adding baffles, then it’s a typical internal sump setup. No issue with that, my FijiCube insert worked well. I am just trying to get more mid water column flow, rather than just skimming the surface water.

 

[Besieged]

Yes, I would say egg crate might be the better retaining method, especially if you can find it in black. Or maybe have something 3d-printed to suit.