Freshwater sump?!

My design has an initial an over baffle prior to the foam pads. That gave me the option for some pre-filtering or just a settlement area filled with Mech or something like that. Then came the foam pads. My intent was to stop at the 45 PPI foam pad, but you could put filter floss or micron filter material after that. Then another baffle just to keep things separate. A light diffuser grating might suffice there. Then the denitrifying media. My original thought was Biohome but the Dr. Novak biocenosis baskets filled with cat litter and laterite seed a much cheaper way to go, so I might experiment with that. Then another pair of baffles. Not sure a pair is really needed, but you only get one chance to get the physical arrangement right without tearing it all apart again, so it seemed prudent. The pump and heaters go in the last chamber.

I planned to put light diffuser grating between the foam pads to keep them separate and provide some support in case the foam sagged or bent in the middle. It should also make it a bit easier to pull one out without disrupting the whole thing. If the foam pads are sized so they are an inch above the normal water line but still a few inches below the top of the sump, this will provide for overflow in case one of the pads completely clogs. That seems unlikely if you're paying any attention at all, but plan for the worst.

Here's a top down diagram of my initial plan using the full width of a 20 long tank.


The green lines represent baffles that water flows over, red lines baffles that water flows under, and purple are diffuser gratings. Water enters on the left and flows to the right.

I rather quickly abandoned this idea for the one with the divider running down the middle of the sump so I didn't get this one fully developed.

 

Ok so thanks to your advice, I spent the morning doing research watching videos and talking to the owner of Swiss tropicals, I've decided to run a foam only sump that will cover both my mechanical and biological filtration needs, and like you said it will cut my maintenance way way down.

Swiss Tropicals is an excellent choice. My only concern would be that 18" of foam might be a bit wiggly in the middle with only the ends secured, but you can always add diffuser grating later if needed. Perhaps the 3" foam is sufficiently rigid that this won't be a problem. The fact that nothing is siliconed in place also makes it very easy to rearrange if you decide to shift things later on.

I'm very curious how the Poret-aqua cubes will work out. By just dumping them in, with gaps around the edges of the cubes, the water should mostly flow over the surface of the cubes, allowing anoxic zones to form inside the cubes and harbor bacteria that will devour nitrates. Did you discuss this with Stephan? I've been curious if he has a recommendation for quantity to deal with nitrates.

 

I was also thinking about adding the baffels and grates much like your arrangement, possibly holding the grates in place with a piece of 1/4 glass on either side silliconed into place for support adding to the ease of removal and cleaning. Or maybe just the grates with no support.

 

I haven't discussed the nitrate removal of the cubes with him yet, iv asked so many qustion already, but he did say that I would have enough of my foam leftover after I cut to fit to make 4gallons of media witch I'm assuming will be enough but I will ask.

 

I've just been curious about the nitrate processing. I've seen it mentioned but haven't seen anything about how much media would be needed or how exactly it works. I've surmised that the inner portions of the cubes become anoxic zones, but that's just deduction on my part with no confirmation. The moving bed idea seems somewhat contrary to that notion since having the cubes moving and heavily aerated water flowing past them should force oxygenated water deeper into the cubes, reducing the size of the anoxic zone.

Since you'll obviously have more than enough aerobic filtration with the foam pads, it would appear prudent to maximize the anoxic zones within the cubes.

I think one benefit of having at least an initial landing area with a baffle separating it from the foam pads is trying to isolate as much of the heaviest muck as possible. Filling that initial area with ceramic rings and having an overflow baffle should keep the heaviest stuff in that first chamber. You'd have to vacuum it out, but that's probably easier than taking one of those large foam pads to the sink for cleaning.

If you get any info about nitrate processing, be sure to share it here.

 

I like the sponge design .
I might want some poly fiber/cut to fit in front of all for an easier to clean mechanical, but you will be fine with your plans ..
I use 2" poret as the last stage in my sump and even with 100 micron pad in front of sponge it stays in place ..The pad needs almost daily cleaning but if I mis the water easily goes over and just through the sponge ..I run my Jeboa 15,000LPH full speed...
Poret is good stuff and Dr.Steve and Swiss Tropicals are good stuff also ..
Nice !

 

I've just been curious about the nitrate processing. I've seen it mentioned but haven't seen anything about how much media would be needed or how exactly it works. I've surmised that the inner portions of the cubes become anoxic zones, but that's just deduction on my part with no confirmation. The moving bed idea seems somewhat contrary to that notion since having the cubes moving and heavily aerated water flowing past them should force oxygenated water deeper into the cubes, reducing the size of the anoxic zone.

Since you'll obviously have more than enough aerobic filtration with the foam pads, it would appear prudent to maximize the anoxic zones within the cubes.

I think one benefit of having at least an initial landing area with a baffle separating it from the foam pads is trying to isolate as much of the heaviest muck as possible. Filling that initial area with ceramic rings and having an overflow baffle should keep the heaviest stuff in that first chamber. You'd have to vacuum it out, but that's probably easier than taking one of those large foam pads to the sink for cleaning.

If you get any info about nitrate processing, be sure to share it here.

this is what he sent me when I asked him about the aqua cubes and nitrates
Aquarium Biofiltration - SWISSTROPICALS

 

I like the sponge design .
I might want some poly fiber/cut to fit in front of all for an easier to clean mechanical, but you will be fine with your plans ..
I use 2" poret as the last stage in my sump and even with 100 micron pad in front of sponge it stays in place ..The pad needs almost daily cleaning but if I mis the water easily goes over and just through the sponge ..I run my Jeboa 15,000LPH full speed...
Poret is good stuff and Dr.Steve and Swiss Tropicals are good stuff also ..
Nice !

Thanks! I appreciate the input!

 

Can you use a 55 gallon instead of a 40 gallon ?

Although a foot longer, it's 6" narrower and slightly taller.

That may open up some possibilities for the design.

 

Can you use a 55 gallon instead of a 40 gallon ?

Although a foot longer, it's 6" narrower and slightly taller.

That may open up some possibilities for the design.

Not really, I got the 40b on sale from Petco for $50 it was a good deal and it fits well under my tank, I really wouldn't want it any taller.

 

If you decide to go with an initial baffle, I'd suggest putting about 6" of some ceramic media (or glass marbles) at the bottom of the first section and run the intake down to that point. Then put a piece of the 10PPI foam on top, making a cutout for the intake pipe. The flow would be into the ceramic media, up through the foam, and then over the first baffle. Now you've got a 3" pre-filter with a primary settlement area below. This should keep the worst of the muck away from your main filter media and allow it to go a lot longer between cleanings. Cleaning out one long, narrow sponge every couple months shouldn't be too bad. If it traps the worst of the muck I'd wager you could go years before needing to clean the first large foam pad.

 

If you decide to go with an initial baffle, I'd suggest putting about 6" of some ceramic media (or glass marbles) at the bottom of the first section and run the intake down to that point. Then put a piece of the 10PPI foam on top, making a cutout for the intake pipe. The flow would be into the ceramic media, up through the foam, and then over the first baffle. Now you've got a 3" pre-filter with a primary settlement area below. This should keep the worst of the muck away from your main filter media and allow it to go a lot longer between cleanings. Cleaning out one long, narrow sponge every couple months shouldn't be too bad. If it traps the worst of the muck I'd wager you could go years before needing to clean the first large foam pad.

That's a cool idea, But I don't think I'm going to add an initial baffle, just one at the end for a optional polishing pad and pretty much stick to the design that Stephan laid out for me.

I like your marble sponge pre filter idea though. I was thinking of a container that was 9-10 inches tall and the depth of the sump but so it could still be pulled out like a Tupperware or something that you could make a removable pre filter with the 6" of marbles and 3 inches of 10ppI foam. With an idea like that I could add at after the fact with no need for baffels and it would make cleaning it a breeze.

 

I like your marble sponge pre filter idea though. I was thinking of a container that was 9-10 inches tall and the depth of the sump but so it could still be pulled out like a Tupperware or something that you could make a removable pre filter with the 6" of marbles and 3 inches of 10ppI foam. With an idea like that I could add at after the fact with no need for baffels and it would make cleaning it a breeze.

The only problem I see with that is if it starts to clog it will block the water flow. If it isn't sealed, then you've got water on floor. If it is sealed, then you've got water backing up into the tank. The pump will just about drain the sump before it runs dry, so you'd need room for about 30 more gallons in the main tank or, again, water all over the floor.

For canister filters I really like the idea of a pre-filter canister that's easy to clean, but I'm not sure it's such a great idea for a sump.

 

I see what your saying. I do have an emergency drain, but still not a good idea.

 

My favorite and last freshwater sump ...






Water overflows first baffle and then gose through a pile of mechanical media [pads and spiral material to separate] under baffle and through first sponge.
Then through sponges the rest of way .The flows length wise for more place for sponges and water ..There many more sponges in it now .Made in a 20 long filtering a 75 gallon .
Less over under baffles held hold co2 for plants ..Baffles are really for marine de gassing and water direction .I total control over where water goes so need only 1 over and 1 under then sponge city !
I took the design from a bud back years ago.

 

That's very close to what I'd planned for a sump with a 20 long, with the divider down the length to get two long runs about 6" wide each. I was going to put another piece of glass across the width where you've got the free end. I figured it would add a bit of strength and also give me a spot to use if a fish needed a respite from the community or to add some water lettuce for additional filtration.

I'm glad to hear you like it. Make me more confident I was on the right track. If I ever get that 100 gallon tank I'll know what to do about filtration.