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1ppm Ammonia --> 1ppm Nitrite? Seeking chemistry expert

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If I have 1ppm of ammonia out of my tap that's going into my tank does that mean I will have 1ppm of nitrite then 1 ppm of nitrate as the nitrification reaction proceeds? Say if I'm doing a 50% water change that will immediately be cut in half- so 0.5ppm of ammonia turns to 0.5ppm nitrite (scary!) and hopefully QUICKLY turns to 0.5ppm nitrate (safe). I don't have any idea what the rate of reaction is but this seems sketchy for my fish at any rate.

It looks like the nitrogen is conserved throughout the reaction from looking at the equations on this page: https://study.com/academy/lesson/nitrification-definition-cycle-equation.html

Best I can tell is the nitrogen is conserved during the nitrification process and oxygen is consumed, or are the oxygen molecules coming from CO2 fixation? Is there someone with a bit more chemistry background or solid understanding of the process that can comment?

I think they are also photophobic so any light coming into the filter will impede their growth? Particularly a UV sterilizer leaking light into the rest of the filter perhaps?
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No offense intended, but you just might be making mountains out of mole hills. To be concerned about small values and their conversion rates serves little purpose. Heck, way back in the day, we knew nothing of BB and yet somehow the hobby survived and fish grew. Okay, there were some losses, but life went on!

Simply put, BB will quickly convert ammonia to nitrites (nitrosomona) and nitrites into nitrates (nitrospira). Tank nitrates <=25ppm is okay. To go a step further, you're in the right place.
Fast growing plants (especially floating plants) will convert N2 into plant tissue that is later removed by trimming. Modest routine partial water changes will further ensure ongoing high water quality.
 

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I'm no chemist, but I can tell you that if you have 1ppm ammonia in your tank and do an exact 50% water change using clean, ammonia free, source water (are you saying your tap has 1ppm ammonia?) then yes you will cut the ammonia in half to .5 ppm. However, I do not believe that 1ppm ammonia gets converted to the exact same amount of nitrite (nor will nitrate readings be exactly the same as the original ammonia nor the eventual nitrite).

In a cycled tank this is all a moot point. After the bacteria is established there is no reason to ever see an ammonia or nitrite reading unless something is done that kills off some/all of the bacterial colony. So yes any ammonia and/or nitrite is scary for the fish which is why having a cycled tank/filter is so important. We strive to create an environment that doesnt allow ammonia or nitrite to build up.

Dont worry about light. Other than canister filters every form of filtration out there is exposed to light. The bacteria will grow anywhere and everywhere.
 

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Discussion Starter · #4 ·
I am saying my tap water has 1ppm of amonia and concerned every water change is degrading the water quality rather than improving it.

If I don't dose nitrogen fertilizer the nitrate will be taken up by the plants as long as I balance the fish and plant load.

But if ever week I'm adding ammonia with a water change it's like I'm effectively overstocked with weekly spikes and the tank may never be stable.
..this is my concern.
 

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I looked this number up out of curiosity a while back because it seemed like nitrite would skyrocket from added ammonia, as well as the nitrate at the end of a fishless cycle. A number of different posters across different boards arrived at approximately the following answer based on molecular weights for each molecule:

1 ppm ammonia --> 2.7 ppm nitrite --> 3.6 ppm nitrate
 

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Discussion Starter · #6 ·
Got it. Thanks.
That makes sense (I think)..

Ammonia: 17 g/mol
Nitrite: 46 g/mol
Nitrate: 62 g/mol

46/17 = 2.7 mg/L nitrite from 1 mg/L of ammonia

62/46 x 2.7 = 3.6 mg/L [ppm] nitrate from 1ppm ammonia
 

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Discussion Starter · #8 ·
Both. Ppm could be mg/L or moles/L. It's just a ratio to define the concentration. I think we most directly measure ppm as mg/L with our test kits. Multiplying that by the molecular weight gives how many molecules and so on.

It's not rounding error. NH4 turns to NO2. Oxygen is 16x heavier than hydrogen. Then the nitrogen picks up another oxygen to become NO3.

I think this is a big deal in smaller tanks where we're doing larger percent water changes if the tap has ammonia in it.

I'm sticking with Crystal geyser for now.

Ammonia in tap water would also explain algae troubles since the algae readily takes up ammonia directly without requiring conversion to nitrate first.
 

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Nitrification- two step microbial process in which NH4+ is oxidized to NO3-
2 NH4+ + 3O2 = 2 NO2- + 2 H2O + 4H+ + energy
2NO2- + O2 = 2 NO3-
Can go to N2(gas) under anaerobic conditions).....
https://www.fairbankssoilwater.org/user-files//ChemistryNitrogen.pdf
Follow the number of N's
NOW that said it's not exactly always what you measure..but chemically yes 1=1=1(+1)=2
Ammonia,nitrite,nitrate,nitrogen gas

first step uses oxygen to produce water, energy and protons..
 

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Ammonia in tap water would also explain algae troubles since the algae readily takes up ammonia directly without requiring conversion to nitrate first.

ammonia is necessary (or extremely preferred) for spore germination..




Algae spores eat ammonia (NH4) and algae eats nitrate (NO3) and phosphate (PO4). You have to start adding nitrate (NO3), phosphate (PO4) and all other important nutrients including CO2. It doesn’t make any sense? No, it makes sense. You have to care about your plants, because they aren’t in a good shape right now. Old leaves produce ammonia (NH4) and algae spores become an algae. Fertilizing will cause that your plants will be in a good shape and they won’t produce more ammonia (NH4) so there wont’t be a new algae. Additionaly, healthy plants will eats ammonia so algae spores will suffer. On the other hand, algae which is present in aquarium right now will be grow because it is full-grown algae which eats nitrate (NO3). Yeah, that’s true, but you will remove it after a while and there won’t become another one, because you removed ammonia, so no other spores will become an algae. Pretty cool, isn’t it? If there is an algae bloom in your tank, and you will cut the dosage of fertilizer down, it is the worst you can do because your plants will suffer from lack of nutrients, their leaves will be unsightly and will cause ammonia (NH4) -> algae. Plants have to be healthy, only in that case algae won’t be present in your tank!
Nitrate (NO3) and phosphate (PO4) don?t cause algae. Ammonia does!! - Aquarium-fertilizer.com
 

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If you're that concerned, simply pre-filter your source water for water changes through a product like API Nitra-Zorb.
It removes ammonia, nitrite, and nitrate from water.
It can be recharged many, many times with ordinary salt water.



Alternatively, considering the slight amount, you may be fine with fast growing (especially floating) plants which will covert the toxins into tissue, later removed by trimming.
 
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