Food and its impact on water - ammonia, nitrite, nitrate after 24 hrs

[Jack L]

thought i would share these results, they were NOT what i expected. i was considering moving to theNLS because i assumed beefheart would be worse, and many have stated that dry foods are better than BH and frozen for water quality. i need to test some frozen foods we use next. that is mysis, brine shrimp, glassworms, bloodworms.

I took about 2grams of these foods, soaked them in about 6oz RO water and did some tests after 24 hours are room temp
API ammonia strips (the max level on strips is 6, so maybe it was higher than 6)
Seachem nitrite/nitrate ( did this test twice)

my tap has a lot of nitrate, the RO gets it down to 6

i don't actually understand how 1 has less nitrate than 6.

it would be cool if others did similar tests and shared their results.




Food
Ammonia by Strip
Nitrite Seachem
Nitrate Seachem



1
Our BH Mix (bh, flake(s), spirulina tabs
6
0
0


2
Hikari sinking pellet
3
0
5


3
Freeze Dried Black worm w/ BH
3
.01
6


4
Pure BHeart
6
.05
10


5
New Life Spectrum
3
5
30


6
RO
0
0
6

[DJW]

The amount of nitrogen contained in various foods will be proportional to the amount of protein, but in order for the nitrogen to show up as ammonia, it must be digested by fish or bacteria.

Your results are interesting though. It looks as though something in your BH mix is absorbing or somehow hiding the nitrates. Could it be fat?

Also, the pure beef heart and NLS is full of nitrates? Hard to explain this one.

[Jack L]

The amount of nitrogen contained in various foods will be proportional to the amount of protein, but in order for the nitrogen to show up as ammonia, it must be digested by fish or bacteria.

Your results are interesting though. It looks as though something in your BH mix is absorbing or somehow hiding the nitrates. Could it be fat?

Also, the pure beef heart and NLS is full of nitrates? Hard to explain this one.

the one that makes the least sense to me is my BH mix, as that has BH, 3 different kings of Ken's Flakes, and spirulina pellets and had low numbers. that is actually the one that made me test the water twice.

i was also surprised by NLS, but i have to say the water actually stinks after a day


i honestly don't know what happens to the the food as it is digested by the fish. e.g. does a high nitrate food mean high nitrate waste?

but i think these tests show what happens to leftovers in water, or hung up in socks. it was RO water, and only 24 hrs, so the test would be just what leached out of the food, too fast for bacteria cycle, plus there is ammonia, nitrite and nitrate reading all at same time.

NLS has 2 strikes against it now, the test and the fact that it litterally hits them and they have no interest. so then i smeared it w/ BH and they sucked off the BH and spit out the NLS.

[DJW]

There shouldn't be any nitrates in fish food as far as I know. Just nitrogen in the protein which is metabolized by animals and bacteria, then released in the form of ammonia. In your ammonia numbers in the table are you showing total ammonia or free ammonia? I would think it must be total ammonia since there would be almost zero free ammonia in the low pH of RO water.

The way I think of this is that the rate at which the tank produces nitrates as an end product is equal to the rate at which you throw protein (food) in the tank, minus the amount of nitrogen ingested by plants and algae.

[Jack L]

There shouldn't be any nitrates in fish food as far as I know. Just nitrogen in the protein which is metabolized by animals and bacteria, then released in the form of ammonia. In your ammonia numbers in the table are you showing total ammonia or free ammonia? I would think it must be total ammonia since there would be almost zero free ammonia in the low pH of RO water.

The way I think of this is that the rate at which the tank produces nitrates as an end product is equal to the rate at which you throw protein (food) in the tank, minus the amount of nitrogen ingested by plants and algae.

The ammonia was from api ammonia test strip

Nitrite and nitrate from seachem kit

[Jack L]

91704

[Lilly]

I would hesitate to rely on what test strips offer as results, they a notorious for giving false readings. API master kits are more reliable. Another suggestion for more accurate result would be to feed the food you are testing to group of fish in a tank of water. Starting with a freshly cleaned tank and then offering the same amount of each food over the day and then testing water the following morning you would get a more accurate idea of how much each food fouled the water.

Kudos to you for your effort and I look forward to reading what you decide to do.

[Hart24601]

I would perform a standard curve with those tests for each parameters before drawing any strong conclusions and repeat the food test a few times. Even the best hobby grade test kits have quite a large variation even if they are performed perfectly. Making a standard solution to test along side the food soaking would be interesting. I would make a .5ppm, 1ppm, 5ppm, 10ppm and 30ppm standards from either sodium or potassium nitrate and see how those test as I wouldn't think fresh food would contain many nitrates at all.

Here is a good article about phosphate and food which for reef keepers is generally more concerning, but still interesting.


http://www.advancedaquarist.com/2012/3/chemistry

[Jack L]

I would hesitate to rely on what test strips offer as results, they a notorious for giving false readings. API master kits are more reliable. Another suggestion for more accurate result would be to feed the food you are testing to group of fish in a tank of water. Starting with a freshly cleaned tank and then offering the same amount of each food over the day and then testing water the following morning you would get a more accurate idea of how much each food fouled the water.

Kudos to you for your effort and I look forward to reading what you decide to do.

for a while i used strips and API at the same time, once i got the hang of strips...they were very much in line with each other. the strips have to be read when the directions say, and api i use a timer for 5 mins as it keeps changing.

there are too many variables in the tank. i used RO water as that seems to be the least variable. and the dilution of the tank... i'd have to dump is $$$$$ of food.

[Jack L]

I would perform a standard curve with those tests for each parameters before drawing any strong conclusions and repeat the food test a few times. Even the best hobby grade test kits have quite a large variation even if they are performed perfectly. Making a standard solution to test along side the food soaking would be interesting. I would make a .5ppm, 1ppm, 5ppm, 10ppm and 30ppm standards from either sodium or potassium nitrate and see how those test as I wouldn't think fresh food would contain many nitrates at all.

Here is a good article about phosphate and food which for reef keepers is generally more concerning, but still interesting.


http://www.advancedaquarist.com/2012/3/chemistry

well, the seachem kit comes with a 10 mg/l control vile, and the pure RO water was my reference point. i could to the testing again.
but it gets stranger.

i did the same test with RO and RO plus detritus from being vacuumed out. the RO water read Nitrate 6 to 10 ish. but the RO with the detritus read Zero after 24hr soak.

i was NOT expecting that either.

i will retest at 48hrs, and also use API, though that is just for sanity as they have come out in the same ranges before, just the API is more drops and time.

Maybe i'm going about it all wrong, but it would be great is others did the same test. it seems the conventional wisdom is that BH is a mess compared to commercial prepped....but at least data point says otherwise, more data points would be great.

[DC Discus]

Everyone's recommendations are good!

Couple things to think about while running your tests; the surface area of the food to dissolve in 24h isn't the same among your treatments. In your last test you probably have algal or de-nitritifying bacterial cells in your detrius consuming your NO3. Also you can add binders (agar) to your beefheart to make it less messy, though I had trouble getting the right amount in it. Also, 2 grams of wet food is vastly different then dryer commercial food. As suggested earlier try to compare the percent protein and have your treatments corrected for % protein.

Thanks for your efforts Jack. I enjoy reading them.
Cheers,
DC

[Jack L]

Good point on surface area. I was not really thinking about that I was more trying to simulate the form of what I throw in a tank.

My Beefheart Mix is not very watery. I know the muscle tissue itself holds water though. I added dry flake and spirulina to it. When it thaws no water comes out of it and it holds together. But if I dried it out I guess that would remove some of the dilution factor the water in it adds

[Jack L]

after 48 hrs

RO water read Nitrate 6 ish (definitely less the the 10 control sample from seachem) same as 24 hrs
The RO with the detritus still read Zero after 48 hr soak for nitrite and nitrate same as before but reads ammonia plently maxed the strip.

my misake not testing for ammonia at 24 hrs.

this actually is a result is makes sense and justifies the hassle of vacuuming it out of the top of the sand.

it also makes sense with what is the the ecology of planted aquarium book. where in short she says, gravel on top of dirt, let the detritus go into the gravel and then into the dirt and plants will use it up. plants prefer ammonia over nitrate.

in my sand tank the poo just lays on top of the sand making a mess, feeding the BB and ending up w/ more nitrate.

[Jack L]

One issue with doing these tests is the subjectivity in reading the result. Tests are OK if done at same time for side by side comparisons, but otherwise just too much variability and subtlety in comparing colors