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Can to much liquid fertiliser produce an ammonia spike

Singy 86

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20 Jan 2022
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Just a quick question about fertiliser, I have just upped my dose of fertiliser as I thought the plants could handle it. But I’m getting an ammonia spike could that be because I’m dosing to much fertiliser that the plants aren’t consuming? Any help would be great thanks
 
depends on the fertiliser, if it contains nh4no3 or urea, yes. If not then, no. Tropica is an example of a fertiliser with ammonium.
 
Some test kits detect ammonia NH3, which is highly toxic, as well as the ionized ammonium NH4, which is only toxic at high concentrations, so you can have a false reading. Check the ingredients of the fertilizer. But I suspect the culprit is the test kit. It is difficult to cause toxicity via fertilizers designed for aquariums , even if you overdose several times the recommended dose.
 
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Thanks guys yeah just done some more research it’s the 2hraquarist apt 3 which contains nh3, no3 so I’m guessing I overdosed and tests are reading slight ammonia and nitrates and no nitrite. Will cut back on the dosing or add more plants. It was showing 0.25/0.5 ammonia so I guess I wasn’t over dosing by that much!
 
Some test kits detect ammonia NH3, which is highly toxic, as well as the ionized ammonium NH4, which is only toxic at high concentrations, so you can have a false reading. Check the ingredients of the fertilizer. But I suspect the culprit is the test kit. It is difficult to cause toxicity via fertilizers designed for aquariums , even if you overdose several times the recommended dose.
Agreed.

@Singy 86 Here is a free (toxic) ammonia (NH3) calculator. Say your test kit, such as API, reports 0.25 ppm as Total Ammonia (NH4+NH3) Make SURE that is the case if using the calculator! and your water is 26 C and your pH is 7 your free (toxic NH3) ammonia is 0.0014 ppm. if your pH is more like 6.5 then free ammonia only amounts to 0.0004 ppm. (0.4 Parts Per Billion!). An unanticipated spike in ammonia should always be considered a red flag if you have livestock - having lots of plants is, as always, the best rail guard. As long as your NH3 calculation do not exceed 0.01 ppm I would not panic, but definitely monitor the situation!

Cheers,
Michael
 
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@Gorillastomp I have done and 80% water change and tested a few hours later and ammonia nitrite were zero will check again tomorrow and water change if I need to. The fertiliser is the only thing it can be I think. Thanks for advice
 
@MichaelJ thanks for that calculator really good shows my ammonia is actually tiny but showing about 0.25 on api test thanks
 
Purely anecdotal, but I never saw a bang on zero reading in any of my two tanks - always something indistinguishable between 0 and 0.25 ppm...

I"ve heard a lot of API test kit users say this, I wouldn't worry too much singy86
 
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