Anoxic Filter for reducing nitrates - Biocenosis Clarification Basket

[twentyleagues]

I've got a couple tanks that have these baskets in them. In my pea puffer tank the nitrates are not registered on an api kit after 8 weeks of no water changes. I top it off only. Every 6-8 weeks I clean the glass really good and do a 30% ish water change. Another tank grow out for neolamprologus meeli fry 10g the basket is very small and if I don't do a wc weekly nitrates get to high 20ppm +. Is this scientific? Not at all. Do I think it works when done properly? Possibly. Leaning towards yes. I have one in my fahaka tank also seems to be keeping nitrates low to non-existent for prolonged periods of time. I do more maintenance on the fahaka tank though as it's very messy, but two weeks shows zero. Most of my tanks have plants of some type none are lushly planted as I kill plants. All will develop algae. So it isn't stopping that from happening. But I don't think it's enough algae to remove all of the nitrate. Again I said not really scientific.
For the record I don't like "Dr" Novak like someone else said seems kind of used car salesman. I don't have the extreme dislike I have for some other youtube personalities for him either. I think he brings up stuff that doesn't need brought up and seems a little disingenuous at times.

I can tell you my pond even with all the plants growing out the top and my mixed up 75g with plants also growing out the top need weekly waterchanges to keep the nitrate below 20ppm no baskets in either one.

I plan on setting up two 125s with baskets. I was thinking of setting one up with one without but I don't have the stocking densities of equal proportions to really make a good study of it.

 

[fishdance]

haven't watched the video but anoxic filter baskets with laterite and kitty litter have been successfully used in koi ponds for many years. Have a look at any hard core pond forum.

 

[twentyleagues]

haven't watched the video but anoxic filter baskets with laterite and kitty litter have been successfully used in koi ponds for many years. Have a look at any hard core pond forum.

That is true. It's just not Dr Novak (if he is a Dr) although he takes (kinda) credit for it.

 

[jjohnwm]

"kinda"????

The guy makes it sound as if he has single-handedly discovered internal combustion, cold fusion and time travel all by himself, through sheer force of personal genius...instead of re-packaging and shilling an existing idea.

 

[twentyleagues]

"kinda"????

The guy makes it sound as if he has single-handedly discovered internal combustion, cold fusion and time travel all by himself, through sheer force of personal genius...instead of re-packaging and shilling an existing idea.

I've watched most of the videos and he does "kinda" (lol) give credit to unnamed persons in the development of this filtration. He does leave those people out a lot also. I first heard about this on a koi forum and was directed to his videos and a blog by someone else. I wanted as much info as I could find. So if you can get past his patting himself on his back then the info is good.

 

[brianp]

Check out the following that I found on Youtube by Dr. Kevin Novak - very interesting:

I just build a version of this that I am now trying out on my heavily stocked 75 gallon. I had to strain the kitty litter and still use media bags - as mine was going in the main tank, and not in a sump - too much was falling through the slits. I'll let folks know how this progresses in a couple of months. In the meantime, please advise if anyone else has tried this, and if successful.

Thank you for sharing this information. Like many, messing with the equipment is half the fun. However, in my case, denitrification units don’t have much utility. For me, the nitrate level serves as a useful barometer of general water quality, allowing me to calibrate my water changes. Even if nitrates were zero, you would still have to perform routine water changes to suppress phosphate and organic contaminant levels. The danger is that reducing nitrate levels will discourage individuals from making routine water changes and there are so many pollutants other than nitrate.

 

[SuperNinja]

Has anyone had any success with this?

 

[TwoTankAmin]

I suggest folks do a bit of research into facultative anaerobic bacteria. The are able to use oxygen if it is present but when it is not they can use Nitrate.

If you have a cycled tank you actually have some of these in your tank, However, in most cases you will not really notice them because they are there in small numbers.

Without going into huge detail here, what it takes is massive media with many pathways through it. Over time more aerobic organisms will be colonizing. What then happens is that some pathways through the media will use up all the oxygen in the water. There are facultative anaerobes colonizing in such pathways and when the nitrifiers in these pathways use up the oxygen they create nitrate. So what now reached the facultative bacteria is water lacking oxygen but containing nitrate. So the bacteria will switch to using that. The result is the nitrate is consumed.

One of the types of filters in which the above process establishes are in large, semi-rigid foam filters. The Hamburg MattenFilter is an idea setting for this sort of thing. The foam is massive and presents a ton of routes that water can take through the foam. Given time more of these routes will have water without O but with NO3.

It is important to realize how much internal surface there is in high quality foam and haw many pathways there can be through it. Because the facultative anaerobes can use either O or NO3 when the pathways change the bacteria will sill be there. They just start using the O when the NO3 isn't coming and vice versa.

It takes months for this process to develop inside the foam. But once established, it should be fairly self-sustaining. A part of this process happens because there are many other aerobic bacteria in filters than just the nitrifying ones. It is the massiveness of the media which allows oxygen to be removed from some of he water passing through. However, this process should never reach the point where it compromises DO levels in a tank. There are still many more pathways where the oxygen is not depleted. Plyus the return roils the surfaces which helps bring in oxygen.

There is another benefit to massive media. Inside will be tiny crittters which break down and consume much of the organic waste. What many folks catch in filter floss that is removed by changing it or by rinsing it out are eaten in a Mattenfilter. What comes out the back side of the foam is a fine silt which one can suck out in under a minute. Any that might get back into the water column will get removed via water changes. Some of my tanks with the clearest water have only a Mattenfilter and nothing else.

I am not promoting any product or site, but the best explanation of this can be found here http://www.swisstropicals.com/library/mattenfilter/ There are other brands of foam that will do the job just as well. What I can tell you is large amounts of semi-rigid, porosity controlled foam are one of the best things I have discoverd in the hobby. I only wish I had done it sooner. I even have some of this type of foam in hang-on filters. I cannot remember the last time I used a nitrate test kit.

 

[duanes]

I'm using one of these Swiss Tropicals Matten/Porret foam blocks in my system. It covers one end of a 125 gallon sump (20" tall x 21" across x 2" thick.

I've used some of the trimmings to block off the pump, from som bio-media (a lava block, and some ceramic rings).


I'm not sure if it has developed anoxic intersticial areas that consume nitrate, because with my normal 30-40% every other day water changes, and heavy aquatic, semi-aquatic and terrestrial plantings I never get detectable nitrate anyway, and didn't get it before adding Matten.

It works great collecting debris, and is easy to clean, I just pull it, toss on the patio, and hose down.
Since I also consider the sump a refugium, it is also filled with plants, and lots of shrimp that patrol the foam block, breaking down debris into smaller bits.

So whether the anoxic bit is legit or not, doesn't matter to me, the other benefits of using Porrett foam for filtration are great in their own right.

Above are some of the terrestrial plants growing on the surface of the main tank, filtered by the Porrett Foam in the attached sump.

 

[TwoTankAmin]

The best filter one can have in a fw tank are live plants in the substrate. They will carry most of the load re nitrifrication. Plants consume ammonium (NH4) faster than the bacteria consume ammonia (NH3). When the bacteria consume ammonia, it ends up as nitrate via nitrite. When plants consume ammonia they basically make oxygen not nitrate. Things go even farther.

In an unplanted substrate the is no real oxygen below an inch deep and often it is less. However, The roots of plants are much deeper in what is normally an anaerobic zone. What some plants do is transport oxygen down to the roots where it is released. This turns the area around the root aerobic which then fosters the growth of the nirtifying bacteria which require O. Now comes the interesting part.

Research shows that when this happens it is followed by two zones- one above and the other below the aerobic zone and these both process nitrate.

Petersen, Nils Risgaard-, Jensen, Kim, (1997), Nitrification and denitrification in the rhizosphere of the aquatic macrophyte Lobelia dortmanna L., Limnology and Oceanography, 42, doi: 10.4319/lo.1997.42.3.0529.

Abstract

Nitrogen and O2 transformations were studied in sediments covered by Lobelia dortmanna L.; a combination of 15N isotope pairing and microsensor (O2, NO3−, and NH4+) techniques were used. Transformation rates and microprofiles were compared with data obtained in bare sediments. The two types of sediment were incubated in doublecompartment chambers connected to a continuous flow-through system.

The presence of L. dortmanna profoundly influenced both the nitrification-denitrification activity and porewater profiles of O2, NO3−, and NH4+ within the sediment. The rate of coupled nitrification-denitrification was greater than sixfold higher in L. dortmnanna-vegetated sediment than in bare sediment throughout the light–dark cycle. Illumination of the Lobelia sediment reduced denitrification activity by ∼30%. In contrast, this process was unaffected by light–dark shifts in the bare sediment. Oxygen microprofiles showed that O2 was released from the L. dortmanna roots to the surrounding sediment both during illumination and in darkness. This release of O2 expanded the oxic sediment volume and stimulated nitrification, shown by the high concentrations of NO3− (∼30 µM) that accumulated within the rhizosphere. Both 15N2 isotope and microsensor data showed that the root-associated nitrification site was surrounded by two sites of denitrification above and below, and this led to a more efficient coupling between nitrification and denitrification in the Lobelia sediment than in the bare sediment.

Full paper here https://aslopubs.onlinelibrary.wiley.com/doi/10.4319/lo.1997.42.3.0529

Other studies indicate there are plants that do the above even more effiiently than the Lobelia used in the above research.

All of my Mattenfilters and Poret cubefilters are on tanks which have no plants. Some also have no substrate. One of the benfits of the Poret is it will ultimtely hold tiny critters which consume a lot of the dissolved organics.

Using a large Poret foam filter is kind of like wearing a belt and suspenders. The fact is that plants in tanks host nitrifying bacteria. And the absolute best filter in a fw tank is the combination of plants and bacteria (as well as other microrganisms). This is how nature does it.