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Testing "Tetra Safestart plus gives false ammonia readings."


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I read that Tetra Safestart plus can give false (falsely high) ammonia readings and that's why you shouldn't check ammonia while using it (some say for a week or two).  I'm not sure how to verify if readings are false in a new tank setup but I thought I'd test if there is any ingredients in the bottle that cause false positives. 

I mixed 1ml of TSS with 500ml tap water and tested it with my API kit, if my back of the envelope math is right that's roughly 40x the recommended dose for a 20g aquarium (my bottle says to use the full bottle for a 20g aquarium, my understanding is the directions have changed over time).  I also tested plain tap water with my kit.  In both cases I saw 0 ammonia. 

I'm curious if anyone else have evidence from a cycling aquarium and other tests showing results one way or the other.  let me know.




Left is the control and right is the TSS dosed water.  the right aged about 10min more then the left.  The camera is also fairly close so the angle from the sun on both tubes then to the camera is different.  The right tube has a bit more shadow.



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The ammonia salicylate method is prone to false positives especially from amino acids. There are a fair number of reports of off-the-charts dark green API ammonia results where the fish are fine. Most of the time this is due to people using Ammo Lock whose SDS indicates it's an amine.

I think with a 40X overdose and no obvious ammonia reading this isn't the case with TSS. Maybe if the bacteria die off and start to decompose.


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