Aquaponic Gardening

A Community and Forum For Aquaponic Gardeners

I've been reading blogs and watching YouTube videos hearing about how ammonia is a killer to your fish. I've tried to take it to heart and try to keep tabs on my ammonia levels. I have an 2 IBCs and 2- 45 gallon aquariums with tilapia fingerlings. My ammonia levels in the aquariums are constantly going high(I mean real high) between 2-5 ppm, sometimes for days. Even so my nitrites are 0 and nitrates are about100. I have never lost a fish. I just did a 20 gallon out 10 gallon in swap ( didn't have enough water ready) and the ammonia is still high. My question is "HAS ANYONE EVER LOST FISH IN A CYCLED TANK TO AMMONIA"? Mine should have died a dozen times.

Views: 473

Reply to This

Replies to This Discussion

Jeff, I recommend that you research the growing awareness about "false ammonia test readings". Many are discovering that they also get elevated ammonia readings when they test their tap water.

If you do, I think it will become clear that the use of chloramine by more and more cities is the source of the ammonia.

Chloramine is a chlorine and ammonia compound with a tight bond that can be broken by the presence of ascorbic acid but not simply by off gassing the way we remove chlorine.

I hope this helps.

Thanks for the tip. I'll test my tap water. BTW when I test using test strips I get a lower reading.


tilapia can handle quite some ammonia. Still, you could get more bio filtration, or feed a little less.

I ordered a new API kit because both of my ammonia kits are older but the new one tests the same as the old ones. I've done 50% water changes and almost stopped feeding but still get the readings. I'm going to assume it hasn't cause a problem because my PH is really low which means my ammonia is actually ammonium which can be processed by the fish.

There are some charts and handy calculations in the discussion linked below, to help you determine when ammonia becomes toxic. It is the un-ionized ammonia that is the problem...

pH (and to lesser extent temperature) will determine the amount of un-ionized (toxic) ammonia in a given body of water.

Hope that helps solve the YouTube (generally not the best source of reliable information) mystery 

(By the way if anyone does happen to read that [milligrams per liter]is the same thing (value) as ppm [parts per million]...)

Great chart Vlad. Based on it I need to start feeding my fish more LOL. Water temps are 80-82, PH is 6 and I struggle to keep ammonia down between 1&2, usually higher. I have 24-  3" Tilapia in a 45 gallon tank (which I plan to move soon) and 7-  6-8" goldfish in another, both with similar #s. I do plan to lower the temps (especially with the gold fish) just have been procrastinating. I've added a potassium hydroxide/hydrated lime solution to raise PH but it goes up a little and drops a lot. I've been monitoring the carbonate, bi-carbonate, hydroxide discussion and it had my head spinning. 

I have a need for some fish water in my garden so I will probably do another big water change.


If you have an API test kit and it reads pH 6 you have no way of knowing what the actual pH is since the kit only reads down to the value 6 (you could be at pH5.5 and it would still read 6. So be careful there...again, If it reads pH6, you really have no way of knowing what your actual pH is.....

You haven't mentioned what your bio-filtration capacity is for those 45 3" fish 

Try adding a bicarbonate buffer and see if after the course of a few weeks it can 'keep up' a bit better with all that nitrification going on.

I'm using a digital tester for PH. I have a 1cu.ft. grow bed and an aquarium filter (rated 50 gallons) that I replaced the carbon pads with poly fiber and still have the bio screens in. What is a good buffer?

For that small of a tank and that many fish, you need to be doing bigger, daily slow water changes of around 80% or higher. You also need to construct a better bio-filter. I would also, for a little buffer, look into adding a very small amount of dolimitic lime or a small amount of a calcium carbonate, complex formulation (not the powder), such as Aragonite sand (with granules 1.5mm~2.0mm or slightly larger). You can also use potassium bicarbonate, but use very little of it and space your dosages 24 hours apart from each other; otherwise, you could shock your fish by increasing the pH too fast in addition to increasing the ammonia's toxicity.

Even though at a pH around 6 the TAN (total ammonia nitrogen) is ammonium (NH4+), which is less toxic for fish, I am guessing that your pH is bouncing back up, whether you notice or not, either due to the water changes or occurrences of algae or changes in the plant's nutrient intake. When the pH bounces back up, then a significant amount of the ammonium converts into ammonia (NH3), which is toxic to fish. Here is a calculator that I have used... CNYKOI - Ammonia Calculator.

TAN slowly changes the body chemistry of the fish's blood. So, right now, you have not yet made any fish sick nor lost any fish. There is a major difference between long term fish damage and  the LC50, that is the mortality rate, of fish versus ammonia.

You are playing a game of russian roulette by allowing the TAN to remain so high.

Quick correction. Appears the website went offline for the calculator that I referenced. Fortunately, a friend introduced me to the Internet Archive Wayback Machine.

Here is the ammonia calculator.

I am getting ready to fill my tanks and start my cycling process, our water has chloromine in it. Has Anyone used "amquel".? Is it safe for fish that we would eat later on? It says it lowers nitrite & Nitrate levels, wouldn't this be counter productive or do you think it would level out.?

I bought some Amquel when I fist started and never used it because of the same concerns you have. I recently heard about a product called Prime. It comes recommended by the host of the forum.

Reply to Discussion


© 2024   Created by Sylvia Bernstein.   Powered by

Badges  |  Report an Issue  |  Terms of Service