MFK Characterization of anoxic filtration.

[NetMax]

There appears to be sufficient anecdotal evidence that biocenosis baskets (laterite inside unscented, non-clumping cat litter, eg: bentonite clay) can convert nitrates (NO3) into harmless nitrogen gas (N3). As an alternative to Dr.Novak's videos, I found this article provided a well balanced practical/technical description: http://mankysanke.co.uk/html/anoxic_filtration.html

However without characterization (eg: ratio of laterite to clay, depth of clay to laterite surface, flow rate, anoxic bacteria species & environmental requirements), this bio-filter's potential in fish-keeping will not soon be exploited. As an inexpensive DIY filter, few manufacturer's are going to invest time/money in scaling something to potentially compete with their existing systems, and if they were doing some testing, they would be keeping their results secret.

This leaves the fish-keeping community to do the analysis - however incidental experiments without controls or scientific method will not produce the results needed. Uncontrolled experiments may in fact set us back - without characterization, many setups will fail (wrong clay dissolving in water, wrong flow rates creating anaerobic or aerobic nitrifying cultures etc). I have the time (recently retired) and a semi-useful background (test engineer, 1/2 century in fish-keeping & worked in fish retail trade) to take this on 'with help' (I have zero academic chemical or biological education).

My current plan is to use a 40g tank as a nitrate source. I'll use several conventional filters and daily add an amount of household ammonia (eg: extreme fishless cycling). I'll set up several 20g pails with an air stone as testers with varying biocenosis setups. Then I'll bring the NO3 levels up and record results. If a configuration is sufficiently successful, I have an empty 90g with a sump filter, and using the most successful test pail basket's culture, I'll populate the sump filter, move the nitrifying bacteria filters over and continue ammonia dosing.

My equipment needs are a good air pump - I'm thinking of buying a linear air piston pump for the volume/decibel requirements (so if anyone has a recommendation). I'll also require an electronic NO3 tester (so if anyone has a recommendation for one, or a loaner) as liquid re-agent NO3 testing at this frequency would become a PITA. I'll also check with my LFSs to see if they wanted to supply airline, air stones, manifolds etc as a sponsor, though I think it'll be a conflict of interest for them.

I'm happy to share all my results. From the group, I'm looking for #1) suggestions on the test setups which I'll post later, #2) links to anoxic bacteria species, #3) anecdotal information, and at a later stage, #4) volunteers to replicate, validate and build on my results. I'm also interested in the temperature range of anoxic bacteria - for it's potential usage in NO3 reduction (and even NH4?) when fish are in torpor, so #5) volunteers with controlled pond conditions which cool to 4C/39F in the Fall of 2024 would be beneficial (if the results were sufficiently promising).

ps: I put MFK in the subject line in the event this thread gets useful enough to be referenced elsewhere - so the group gets full credit. ?

Comments (and encouragement) appreciated.
Cheers.

 

[esoxlucius]

There are two sides to every argument, and although Dr Novak comes across as completely plausible, a really nice guy actually imo, there are, according to a lot of people, some gaping big holes in his argument. To such a point where his claims are laughed at by many extremely experienced individuals within the scientific community.

If, so far, you've just concentrated on the copious amounts of literature spewed out by Manky Sanke and Kevin Novak, I urge you to dig a little deeper because there is also a lot of stuff completely dissing their claims.

You sound like you are going to invest a lot of time and energy into this, and maybe even money. I'd hate it all to be in vain.

I wish you the best of luck, I will certainly follow your journey through this thread. I hope you can convince more people than Dr Novak has been able to regarding the effectiveness of these BCB's to reduce/eliminate nitrogenous waste.

 

[NetMax]

There are two sides to every argument ... I wish you the best of luck, I will certainly follow your journey through this thread. I hope you can convince more people than Dr Novak has been able to regarding the effectiveness of these BCB's to reduce/eliminate nitrogenous waste.

Agreed, thanks. It's really been some positive but anecdotal feedback that I've gotten from experienced fish-keepers that made me think it was time to quantify the effect (without the variables of fish, substrate and plants) but I always start with a healthy amount of skepticism. Posting the results here (good or bad) allows a level of peer-review to the methodology I'm using, and if it should be modified, and to replicate if needed.
Cheers

 

[NetMax]

Raising this for the possibility of someone knowing of a bulk supplier of laterite in North America. Bulk as I'll need 200lbs eventually if the tests were positive, and North American so others can peer-review my test results. I'd rather not use Flourite as the iron content is much lower and it would be cost-prohibitive in volume. Also some challenge sourcing 5-7.5% natural ammonia. I found a gallon on Amazon of undeclared concentration to start with and hopefully produce enough NO3 for the tests. My planted tanks have zero NO3 (normally not something I 'want' to have).

Thanks

 

[kzimmerman]

You might want to check garden centers for the laterite, they may have it. I've used it professionally before as a grouter, but it was always a powder. Now, is this an absorbent thing? That wouldn't work long term. What happens to the remains of the nitrate? off gassed as oxygen and nitrate? What is the mechanism behind the laterite that would reduce nitrates?

 

[Something Fishy Here]

I'm all for the pursuit of knowledge, and exploring new ways to make our fish healthier and happier, so I hope you the best of luck and have some fun with it! That being said, how is it a conflict of interest for the lfs and existing equipment manufacturers? I easily could be missing something but reducing nitrates wouldn't reduce my need for any current supplies or equipment. My first assumption was reduced water changes, but there's a lot more than nitrates that we're removing with water changes, ie. hormones, particulate waste, etc, that still would still need to be removed but are much harder to see or test for. Again I totally support learning more about our artificial ecosystems, and if it evolved into another filter to hook up to reduce nitrates, great! 1 less thing to worrry about, but my water change and maintenance schedule would likely remain the same. Maybe I'm overlooking something else. Either way good luck and keep us posted, very interesting!

 

[NetMax]

You might want to check garden centers for the laterite, they may have it. I've used it professionally

I'm all for the pursuit of knowledge, and exploring new ways to make our fish healthier and happier, so I hope you the best of luck and have some fun with it! That being said, how is it a conflict of interest for the lfs and existing equipment manufacturers? I easily could be missing something but reducing nitrates wouldn't reduce my need for any current supplies or equipment. My first assumption was reduced water changes, but there's a lot more than nitrates that we're removing with water changes, ie. hormones, particulate waste, etc, that still would still need to be removed but are much harder to see or test for. Again I totally support learning more about our artificial ecosystems, and if it evolved into another filter to hook up to reduce nitrates, great! 1 less thing to worrry about, but my water change and maintenance schedule would likely remain the same. Maybe I'm overlooking something else. Either way good luck and keep us posted, very interesting!

NO3 is just a convenient chemical marker, and in heavily planted systems, it can't be used as an indicator when water changes are needed to dilute/replenish other elements, such as the minerals making up our typical carbonate buffer to stabilize pH. We can adjust water changes to maintain kH levels, and even move to other markers, but a reduction of NO3 (through anoxic nitrification) doesn't 'necessarily' change our procedures. There are applications where it's desirable to have very low NO3 (eg: fry grow-out), or where aerobic nitrification doesn't work (low pH) and the system lacks sufficient organic alkalinity to stabile the pH, or there's no mechanism of significance to remove nitrogen products, like over-wintering fish in torpor under ice and their respiration continues to add NH3 into the water around them, or in situations where nitrobacters are inhibited before nitrosomona bacteria (rapid pH or temperature swings) resulting in nitrites being present etc. In typical unplanted large-fish applications, where it's not practical to have a continuous wetland/bog nitrogen sink working in parallel, the anoxic culture might only result in lower NO3 between existing water changes, and likely make our existing nitrifiers more efficient. All that to say, there's many different applications where an additional nitrogen consumer could be a valuable tool for water quality management, and while it's not my intent, could even reduce our consumption of water. A possible conflict of interest to OEM is the introduction of what could possibly be another easy DIY nitrifier which they can't monetize (they've been looking at anaerobic variants for over 50 years) and 'if' it could perform basic NH3/4-NO2-NO3 nitrification + NO3-N3, a DIY filter would reduce their aerobic filter & media sales. I wouldn't be surprised if the OEMs have something ready to release to market if anoxic were effective, characterized and scaled for recreational aquarium use, just to mitigate their losses.

 

[kzimmerman]

Another very important problem with anoxic processes is the production of hydrogen sulfide. That's not fun stuff to mess around in.

 

[NetMax]

I've been unable to source bulk laterite or bulk ammonia to perform the tests, so I've given up. I'll get rid of my nitrates the old fashioned ways, plants, bog plants and outside I might try some aquaponics (why I needed 'bulk'). I think the development proceeds though, under the term 'anammox bacteria'. Meanwhile I'm at a loss as to what I'm going to do with the dozen 20g pails I got for the anoxic test. https://www.zeolite-anammox.com/what-is-zeolite-anammox

 

[Iwhoopedbatman]

I've been running anoxic for about a year and a half. It works. My nitrates aren't always 0, but they stay below 20 ppm long term once the tanks are broken in (seems to be mostly luck how long that takes, some took a couple months, others took 6) and my lighter stocked tanks do stay at 0. The most interesting thing when I converted my first 4 tanks is how much more stable everything is and how much maintenance it saved me. I now have 11 tanks running and I still have fewer issues than when it was just 4 using traditional filtration with lots of pothos and peace lilies (I still use these on the 3 biggest tanks). All have plenums. The larger ones (55 gallons and up) use BCBs in sumps and/or canisters as well. I've been incredibly impressed personally. If laterite is an issue to source, you can use a little Seachem Flourite instead as an iron source. I use generic clay oil absorbent as the main media. Best thing about the clay is that you will never get ammonia spikes. You can see nitrites for a couple days when it's going through the initial cycle, but never ammonia.