My Cod These Denitrification Results!!!

So I have a plastic trashcan in my garage that I have filled with all sorts of biomedia - ceramic rings and balls, lava stone, pumice, bio balls, plastic pot scrubbies, yada yada yada.

For months and months I've been adding pure (or almost pure) ammonia to it, several ml each day.

And the beneficial bacteria would literally chew through that stuff QUICK. Whenever I tested, no ammonia or nitrite.

But, that is where the process stopped. Nitrates stayed dark, dark red for months.

I have an air pump hooked up to it, so I through maybe if I stop feeding it oxygen the denitrification will start. So I unplugged the air pump. Months after that, still nothing (and, interestingly, without the air pump the ammonia and nitrites started building up FAST - and as soon as I turned the air pump back on they dropped equally as fast - goes to show you the need to a good O2 source).

So I remembered coralbandit said he did not think denitrification would work without a carbon source.

So I turned the air pump back off and started dosing vodka. A few ML a day or every other day.

The results, after 2 or 3 weeks? See below. Freaking zero nitrates or as close to it as one can realistically get I would guess.

Bottom line is if carbon dosing isn't absolutely necessary, it will help a TON.

Now I am going to turn the air pump back on, keep adding ammonia, and also keep adding vodka, to see if my contraption, which I call DeNitroSlice, can continue to do its thing on all of those three baddies at once.

Also, I have a 55 gallon tank with like 4 or 5 inches of substrate at the bottom, where most of that is biological media with sand covering it all. So the flow there is very low for sure, and plenty of room for denitrifying bacteria, so I am going to start vodka dosing as well.

If anyone has any similar experimental ideas, I'm all ears!

So if this is successful in making ammonia, nitrites and nitrates all go bye-bye, isn't a true no-water change tank basically here? (maybe a few plants to try and help filter out the much smaller things like fish hormones or whatever I see people talk about that can build up but much, much more slowly)

Left ammonia, then nitrites, then nitrates. WOW.

I don't know why pictures do not seem to be working. Grrrrr...

 

Pictures are currently broken, hopefully it's fixed soon.

 

Nice !
The amount of vodka needed is so little it is a no brainer .
Just have to remember to dose daily or even better 2x a day ..
Have you thought about a dosing pump ?
I would think water changes are still needed as trace elements will be used up or exhausted.
Just like a reef tank but you really don't have the supplements to add and water changes are cheap !

 

I'm still really new to the hobby and chemistry in general, how is the vodka a carbon source? The sugars?

 

Other than cleaning the debris off of the bottom of the tank.

 

There are many articles on carbon dosing . Some use vinegar,sugar ,vitamin C or vodka .
I have used all on my reef tank before to control nitrates .

 

Not wanting to rain on your parade, an all. But I use Seachem Matrix in both my canister filters which are giving me a complete cycle, 0,0,0 with just a 10% weekly wc on a 465lt well stocked tropical setup. Now only water change to clean sand and replace trace elements.

 

I'm still really new to the hobby and chemistry in general, how is the vodka a carbon source? The sugars?

I'm guessing it would be the ethanol. C2H6O.

Tony.

 

I just achieved 0,0,0 after 4 weeks with Pond Matrix in my 150 gallon stock tank with a SunSun 304B canister. I don't add any carbon source. but I think fish poop, and some decaying plant matter works just as well.

but instead of weekly 50% water changes i'm doing every 2 weeks 50% water changes now. you're not just removing nitrate during water changes. you're also removing other stuff. and replenishing minerals that have been consumed by the bacteria, plants, fish, etc.
https://www.fishlore.com/aquariumfishforum/threads/large-or-small-water-changes-discussion.393921/

 

I'm guessing it would be the ethanol. C2H6O.

Tony.

I've heard of using chelated iron to help facilitate denitrification also. Whatever works. Just use cheap vodka.

 

Not wanting to rain on your parade, an all. But I use Seachem Matrix in both my canister filters which are giving me a complete cycle, 0,0,0 with just a 10% weekly wc on a 465lt well stocked tropical setup. Now only water change to clean sand and replace trace elements.

Yes but he is using a pretty much sterile environment. I'd bet you have things decaying in your tank as a carbon source.

Homeslice thanks for doing this and posting it. I'm going to setup my bucket test and see how much ppm 1 cup of bio rings can handle all the way to nitrate. Its experiments like these that help us all, until they are buried and forgotten in a year lol.

I'm also contemplating setting something up to measure the results of septic tank additives. Who know vodka dosing would help for freshwater lol. Good intuition!

 

Lets not forget that in marine application where this was developed [I believe ] a protein skimmer is incorporated to remove the result of the process.
be it bacteria or by product there is still something that needs to be removed so water changes can be omitted under my understanding ?
The lack of what the protein skimmer removes is why this is not a long term solution in FW.
Now doing this before water changes? That might get us closer to natural quality water .I believe barley does the same thing also ?
Many use that in ponds ...

 

Yes but he is using a pretty much sterile environment. I'd bet you have things decaying in your tank as a carbon source.

Homeslice thanks for doing this and posting it. I'm going to setup my bucket test and see how much ppm 1 cup of bio rings can handle all the way to nitrate. Its experiments like these that help us all, until they are buried and forgotten in a year lol.

I'm also contemplating setting something up to measure the results of septic tank additives. Who know vodka dosing would help for freshwater lol. Good intuition!

Thanks Wraithen! Yea, I love sciencing this stuff up to help not just myself but hopefully the community. And, I must admit, I didn't come up with vodka on my own - start at around 14:30 of the attached.

Lets not forget that in marine application where this was developed [I believe ] a protein skimmer is incorporated to remove the result of the process.
be it bacteria or by product there is still something that needs to be removed so water changes can be omitted under my understanding ?
The lack of what the protein skimmer removes is why this is not a long term solution in FW.
Now doing this before water changes? That might get us closer to natural quality water .I believe barley does the same thing also ?
Many use that in ponds ...

That was my next question coralbandit - so the denitrification is complete, what does that leave behind? How do we get rid of that? If its just protein, do they make (or can one DIY) a protein skimmer for freshwater? I need to science those! Thanks!

 

Thanks Wraithen! Yea, I love sciencing this stuff up to help not just myself but hopefully the community. And, I must admit, I didn't come up with vodka on my own - start at around 14:30 of the attached.

That's a good video. What he says at the end with the clay material is what Seachem says about Matrix.

Matrix is extremely porous so the majority of its surface area is internal. The pores allow water to penetrate throughout the media but restrict its flow. Aerobic bacteria colonize near the surface where oxygen is plentiful, but use up the oxygen leaving the interior anaerobic and allowing denitrifying bacteria to thrive.

They clay he shows is about the size of Seachem Denitrate, smaller version of Matrix. The larger regular Matrix and even bigger Pond Matrix is what you need if you don't have the smaller flow. I only do water changes once a month due to the denitrifying process achieved.

 

That was my next question coralbandit - so the denitrification is complete, what does that leave behind? How do we get rid of that? If its just protein, do they make (or can one DIY) a protein skimmer for freshwater? I need to science those! Thanks!

Protein skimmers work to remove waste before it can break down into nitrites/nitrates. The surface tension of normal fresh water doesn't allow stable bubbles form and linger long enough attract the organics out of the water. It's actually a way better filtration system, rather than what we use on Freshwater that just collects and breaks down the waste.

 

That was my next question coralbandit - so the denitrification is complete, what does that leave behind? How do we get rid of that? If its just protein, do they make (or can one DIY) a protein skimmer for freshwater? I need to science those! Thanks!

If I remember correctly, some of it goes back to being ammonia, but there's a fair amount converted to nitrogen which gasses off.

 

If I remember correctly, some of it goes back to being ammonia, but there's a fair amount converted to nitrogen which gasses off.

Interesting - I know there is gas off - is the rest really just back to ammonia? If so I would think that would be a great answer, since we already have the bacteria in place to finish off that remaining ammonia!

 

Interesting - I know there is gas off - is the rest really just back to ammonia? If so I would think that would be a great answer, since we already have the bacteria in place to finish off that remaining ammonia!

Which is exactly why you test 0s. It just recycles back and forth to nothing

 

different types of denitrification

"Ion exchange: In this chemical process, unwanted dissolved ions in water, such as nitrates from fertilizer, are exchanged for similarly charged ions as they pass over a bed of resin beads.

Biological denitrification (activated sludge) process: Microbes do most of the work in biological denitrification. Commonly used bacteria that can use oxidized nitrogen — denitrifiers — include Pseudomonas, Alcaligenes, and Paracoccus. When they break down NO3 to metabolize oxygen, nitrogen gas is released.

Chemical reduction: In these processes, chemicals such as acids are used as reducing agents to form ammonia or elemental nitrogen. These processes often require special conditions, such as the use of catalysts, or high heat and pressure." https://www.environmental-expert.com/articles/what-is-denitrification-801007

"One major application of denitrification is in water purification. Denitrification can remove nitrogen species from water in the form nitrogen gas. Denitrification can be done in three methods for water treatment: ion exchange, chemical reduction, and biological denitrification."
https://pediaa.com/difference-between-nitrification-and-denitrification/

the method we use is biological, which produces Nitrogen gas.

 

edit; what Skavatar said.

 

Thanks ladies and gents! So if the denitrification releases gas which leaves the tank, and ammonia which stays in the tank but which is itself quickly run through the process again and which is itself eventually gassed off, what is left behind that needs to be taken care of to try and avoid water changes? Phosphates maybe? Excess minerals as water evaporates leaving minerals behind and new water is added itself having minerals, etc.? I saw someone mention "fish hormones" or something one time? I would LOVE to get to a point where water changes are nonexistent or very, very infrequent.

Thanks!

 

You get nutrient depletion, tds buildup, hormones and allelopathy are also thrown around. Back when my nitrates were in check I did monthly water changes, but then I left and sometimes my wife would take a couple or 3 months between them.

 

You get nutrient depletion, tds buildup, hormones and allelopathy are also thrown around. Back when my nitrates were in check I did monthly water changes, but then I left and sometimes my wife would take a couple or 3 months between them.

Oh wow, lots of stuff to worry about! Nutrient depletion - could you just add some all-in-one mineral addition to tackle this angle? With respect to the others, if you had a few plants might they remedy the issue? Obviously having 1 fish in a tank with 100 plants they could, but I am just trying to figure out if you achieve denitrification, and have [20] fish in with [3] plant, you could effectively do away with water changes. Thanks!

 

Oh wow, lots of stuff to worry about! Nutrient depletion - could you just add some all-in-one mineral addition to tackle this angle? With respect to the others, if you had a few plants might they remedy the issue? Obviously having 1 fish in a tank with 100 plants they could, but I am just trying to figure out if you achieve denitrification, and have [20] fish in with [3] plant, you could effectively do away with water changes. Thanks!

You could theoretically. If you could test for every known compound required and what levels you needed and could add them individually you could do that. You would still have things building up though. There's plenty of tanks that never get water changes. The biggest kick in the gut for me was when I came home, the only things that were still alive in the plant department were wisteria, crypts, ar, swords, some dwarf sag that didn't get bigger or throw runners, and tons and tons of jungle val. The jungle val was the king at keeping everything else stunted. Once I took a bunch out everything else started growing again.

 

you could look into the Walstad Method.

 

Back in the day [before venturI skimmers ] discus breeders used protein skimmers ..
They did this with old school skimmers that had air injected through lime wood diffusers.
To make the air stickier they used ozone generators...Without ozone protein skimmers do not work in fresh water ..
No real new science ..Oldschool...