A bottom of the tank Matten filter?

[anewbie]

On 1/30/2022 at 3:52 PM, HH Morant said:

I think getting a biological filter really clean is bad because it means cleaning away the gunk where a lot of the beneficial bacteria live. If foam is used for biological filtration, it is generally best to use foam that is course enough (30 ppi) that it does not clog easily and can be left in place for months without cleaning. But the cleaning should just be an un-clogging, not a thorough cleaning.

One of the interesting things about this experiment is that 40 ppi foam is being used. While 40 ppi might clog too readily in a canister or sump, the flow rate with an under-gravel filter is slower, so maybe that will make the difference. 

Cleaning the foam in place (rather than taking it out) would be best, and @gardenman has plans for that. We'll have to see how it works. Because getting the foam perfectly clean is not the goal, maybe it will.

@gardenman, I appreciate the idea, the effort, and the reporting. Thanks.

That would be logical but all the studies i've seen have shown this to be false. Removing the gunk doesn't harm the bacteria and the reason to remove the gunk it is clog the spong and reduces the flow of water.

[anewbie]

On 2/8/2022 at 3:19 PM, HH Morant said:

@gardenman, there is now an article at aquariumscience.org dedicated to you and your bottom-of-the-tank Matten filter. The author (Dave) thinks it is a great idea:

2022-01-24 Added an article on “8.7.7. Bottom of Tank Matten Filter”

Today in the comments:

Dave says:

In reply to Scott …. It has a very large surface area and void volume. So under “normal” circumstances it wouldn’t plug up. The rate of decomposition of the “brown gunk” would be greater than the rate of deposition. But there are extreme circumstances which could change that. A food with low protein content, very heavy stocking, heavy feeding, low aeration, no good inoculate during cycling: can all combine to create plugging. But it has to be extreme. And yes, plants will root in it but as long as the tank is reasonably stocked, reasonably fed with a high protein food, properly inoculated and reasonably aerated one does not need to worry about plugging. I go into this in greater depth in this article https://aquariumscience.org/index.php/18-5-heavy-stocked-maintenance/

Scott Mitchell says

Hi Dave,
The bottom of the tank matten seems like a great biofilter but unlike an under gravel would it not plug up eventually?
I just can’t see how it could not. Could you explain why it wouldn’t or is this just considered ‘ok’ and just needs maintenance? I just would not want to take the whole thing out to clean it up and reinstall, especially if plants have rooted in it!
Thanks.

Maybe after I move I'll spend three years testing this but my guess is that he is wrong; and it will clog over time. Of course his logic is a lightly stocked cichlid tank (such as a 20 long with 1 pair of hongsloi) might be fine; but if you go for those algae eaters (bn pleco, guppies, swordtails, ...) good luck.... Lets consider for example a sump composed of a series of sponges (same idea really); you might not need to clean it daily but after 8 or 12 months a few of those sponges might show sign of clogging but still work; but after 2 years.... you might see serious drop in water flow through the sponges. Of course diet and stocking does impact duration but my experience with matten fitlers in community tank show that they clog after 8 to 12 months. Now the flow through the sponge on the bottom might be slower but on the converse side you won't be able to readily measure flow to determine if there is an issue. Anyway I have no doubt it will work effectively for 6 or even 12 months; but lets check it after 3 years.

[gardenman]

If I can go three years without the filter clogging, I'd consider that a huge win. What other filter runs for years between maintenance? If it goes six months before clogging I'd be happy. Six months of a largely maintenance free tank is pretty good. I'll take that. It was started at the end of November so it's been about two and a half months so far without issues. If it never needs cleaning, so much the better, but it's already doing very well. I have no complaints.

[Odd Duck]

Hey @gardenman Look what I did today!  10 gallon, looking at it endwise.  Still has an ACO filter in it, but I plan to do similar to what you did, give it 2-3 weeks to seed the matten, then pull it.

 

[gardenman]

Looking good! I gave mine six weeks to seed the Matten sponge, but I have a large bioload and may have been overly cautious. Your wood and plants may already have enough bacteria to handle whatever fish you put in. It's a pretty neat little system. Lots of sponge surface area. All kinds of life settles in the sponge. A tank like this would be neat in a high school bio classroom. I'll plop down and just stare at the sponge for a while and watch all the little stuff inside it moving. From time to time a little worm will climb out of the sponge and meander across the surface to a new spot and burrow back down into the foam. The foam becomes a pretty neat little ecosystem within the tank. I suspect all of the stuff I'm seeing living in the foam is in a regular gravel tank, but you don't see it there. In the foam against the glass you can see all of the life and there's a lot of it. It's pretty neat.

[Odd Duck]

On 2/13/2022 at 9:05 AM, gardenman said:

Looking good! I gave mine six weeks to seed the Matten sponge, but I have a large bioload and may have been overly cautious. Your wood and plants may already have enough bacteria to handle whatever fish you put in. It's a pretty neat little system. Lots of sponge surface area. All kinds of life settles in the sponge. A tank like this would be neat in a high school bio classroom. I'll plop down and just stare at the sponge for a while and watch all the little stuff inside it moving. From time to time a little worm will climb out of the sponge and meander across the surface to a new spot and burrow back down into the foam. The foam becomes a pretty neat little ecosystem within the tank. I suspect all of the stuff I'm seeing living in the foam is in a regular gravel tank, but you don't see it there. In the foam against the glass you can see all of the life and there's a lot of it. It's pretty neat.

I don’t have any fish and may only be adding shrimp and nothing else. I’ll let the shrimp slowly build up the filter. The wood carries enough biofilm to feed shrimp, but I want to see what parameters do over the next week or so just from adding the wood and plants.

My “shrimp” tanks have been over run by scuds so this is a do over. I’m sure it will be seeded enough in just a few weeks to start with some “best of the best” from a colony of sapphire shrimp I have in another tank. I’d like to see how they do with the matten bottom. I suspect I could use only 1” foam easily. 

Edited February 14, 2022 by Odd Duck
Fix auto”corrected” typo.

[Vanish]

I think plant roots will eventually bind it, but it is a good idea regardless. I think you would be better off with potted plants on it, but itll probably be good for years.

[gardenman]

Another Saturday and the same old, same old. Everything's going well. The Super Reds had a third spawn but kicked some of the eggs out that hatched outside the cave. The Water Sprite has grown enough to fill in what I'd removed last week. The Anubias are all doing great. The fish are doing great. No issues anywhere. There are lots of healthy, happy, baby plecos in the ten-gallon tank. Unlike my other tanks, the swordtails just ignore these little plecos. The water quality is still excellent. Everything tests fine. No issues at all. It just works.

 

[Torrey]

Your swords are huge!

I haven't kept swords since the 70's, and mine were the all orange variety, generally labeled as generic "swordtail platy"

They were barely bigger bodied than the guppies.

I'm glad they aren't eating your babies in the 10g.

[anewbie]

Yea I have orange swords. I really wanted a nice set of green swordtails but i couldn't find any that i liked. As  kid the local store would have some with really nice deep green stripe the tail and otherwise normal green body. However all they have now are 1/2 green 1/2 orange. These are my orange - the 5 year old male died about 2 months ago but just before he died he had a son; the females are all off spring from the original female and male. The females I frequently give to the petshop as new ones mature (to reduce population) but since the old male died i've not had any frys so i guess this will be the last generation:

Btw my tank has a corner matten rather than a bottom one. There is that open debate (imho) of whether it makes more sense to have it on the bottom or the side; and these debates should also consider flow in the tank as in my case the flow shoots across the surface in the back as oppose to the uplifts. There is of course the trade off of space on the bottom vs the corner as well as the size of the filter and ease of maint. as I can clean mine without tearing up the tank.

 

This aquarium has been setup for 30 months so i have some experience with life cycle of the filter.

 

 

Edited February 19, 2022 by anewbie

[gardenman]

On 2/19/2022 at 3:01 PM, Torrey said:

Your swords are huge!

I haven't kept swords since the 70's, and mine were the all orange variety, generally labeled as generic "swordtail platy"

They were barely bigger bodied than the guppies.

I'm glad they aren't eating your babies in the 10g.

Swordtails can get pretty big. Nose to tip of tail, my bigger males reach about six to seven inches or maybe a bit longer for the biggest. The females reach about four to five inches, but are bulkier. They're a pretty good sized fish. Much bigger than guppies.

[Torrey]

On 2/19/2022 at 3:54 PM, gardenman said:

Swordtails can get pretty big. Nose to tip of tail, my bigger males reach about six to seven inches or maybe a bit longer for the biggest. The females reach about four to five inches, but are bulkier. They're a pretty good sized fish. Much bigger than guppies.

That is a lot bigger than any of the fish we had in our tank.

I wonder if swords in the early 70's just weren't as big? Or, I was too young to be aware of fish dying?

I just know the males' bodies weren't much bigger than the female guppy bodies.🤔

[gardenman]

On 2/20/2022 at 2:36 AM, Torrey said:

That is a lot bigger than any of the fish we had in our tank.

I wonder if swords in the early 70's just weren't as big? Or, I was too young to be aware of fish dying?

I just know the males' bodies weren't much bigger than the female guppy bodies.🤔

Fish grow throughout their lives and my oldest swordtails are my biggest, and they're about four years old. My younger ones are more "normal" swordtail sized (3"-4".) Younger fish will be smaller while older fish will be larger. Age and size are closely related. Some of mine might be pushing five years old now. I had them back before I broke my femur in January 2018, so the oldest guys/gals might be getting closer to five years old. Swordtails typically live 3-5 years and the older fish will be the larger fish.

[anewbie]

On 2/20/2022 at 6:49 AM, gardenman said:

Fish grow throughout their lives and my oldest swordtails are my biggest, and they're about four years old. My younger ones are more "normal" swordtail sized (3"-4".) Younger fish will be smaller while older fish will be larger. Age and size are closely related. Some of mine might be pushing five years old now. I had them back before I broke my femur in January 2018, so the oldest guys/gals might be getting closer to five years old. Swordtails typically live 3-5 years and the older fish will be the larger fish.

My understanding is that non-green ones are really hybrid formed by selective breeding and they have a little platy in them and therefore do not become quite as large. My 5 year old male was long but not 7 inch and he was very lean. The green one are closer to wild swordtails and they do get larger....

Edited February 20, 2022 by anewbie

[Torrey]

On 2/20/2022 at 8:36 AM, anewbie said:

My understanding is that non-green ones are really hybrid formed by selective feeding and they have a little platy in them and therefore do not become quite as large. My 5 year old male was long but not 7 inch and he was very lean. The green one are closer to wild swordtails and they do get larger....

That would explain my memory. 

We bought ours as VERY orange "orange swordtail platies" and the tail was nowhere near as long.

[bela]

I have just discovered this thread and all I can say is WOW.

Congratulations @gardenman

I have been keeping fish for 35 years.

I have UGF in both of my tanks (40 and 15 gallon). They have been running only for a couple of years so I do not intend to take them apart now but, if I get the chance to set up a new tank or if I, for whatever reason, have to reset them, I am trying this method 100%

[gardenman]

On 2/24/2022 at 11:03 AM, bela said:

I have just discovered this thread and all I can say is WOW.

Congratulations @gardenman

I have been keeping fish for 35 years.

I have UGF in both of my tanks (40 and 15 gallon). They have been running only for a couple of years so I do not intend to take them apart now but, if I get the chance to set up a new tank or if I, for whatever reason, have to reset them, I am trying this method 100%

Yeah, so far, so good. It seems to work very well. It made a lot of sense, but I'd never seen it done before.

[gardenman]

I almost forgot it was a Saturday. Apparently I skipped last Saturday also. Nothing new to report. Everything's going great in both tanks. No issues. No deaths. No problems. Just lots of happy, healthy fish.  

[gardenman]

Just an update on the ten-gallon tank. It's about six months now since the setup and when I came back into the room after feeding the fish this morning, I saw the plecos weren't eating their green beans. Something was off. I tested the water, and it was fine. I gave the tank a better look and noticed an abundance of white "stuff" (photo below) in the left uplift tube. I didn't know what it was (still don't) but I knew I didn't want it in there, so I tore the tank down and gave it a good cleaning and did a 70% water change and plopped the fish back in and everyone's happy again. I'm happy to report the filter sponge was not clogged in the least. I took it out on the UG filter plate and held it under the faucet and water ran through it freely. I gave the sponge a good cleaning and everything is back in the tank and doing well again. I have no idea what that white stuff was, but it largely filled the left uplift tube. It's an organic something or other, but other than that I have no idea what it was. I'm assuming it was affecting the fish in some manner, as they're back to normal again now.

[eatyourpeas]

On 6/13/2022 at 7:02 AM, gardenman said:

It's an organic something or other, but other than that I have no idea what it was.

Whatever it is, it appears to be a funky hairy monster ready to jump and attack! Eeek! 🤪

[Guppysnail]

There is no eewww emoji. I’m glad your setup is still working well.

[Patate91]

Any update on your tanks?

[gardenman]

The tanks were working perfectly up to the end of December when I had to shut everything down due to an eviction. When I get my new apartment (late June, July, I was seventh on the wait list as of May first) I'll probably be a bit limited in the tank size allowed due to lease restrictions, but if they let me have a ten gallon tank, I'll probably restart the matten filter project again. I might try a one inch layer of aquarium soil over the filter to help the plants more. (Well, to help me plant the plants more easily. Getting them into the slits in the foam was annoying.) I think any new setup will be a shrimp/nano fish setup. They won't need massive biofiltration, but in my vastly overpopulated tanks, the filters worked great. If I'm forced to a smaller tank (3-5 gallons) I'll probably just go with a normal sponge filter. Everything fish-wise is in a holding pattern for me for now. Once I get the new apartment, things will resume.