Bizarre test results when cycling

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Jekyllandjavert

Aquarium Advice Newbie
Joined
Aug 23, 2021
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2
I am doing a fish-in cycle (I know I know) and I have a 2 part question. First, is there any reason I would be getting some false positives on the nitrite tests? Last Thursday I saw nitrite readings for the first time - between .25 and .5 PPM. Then, when I tested on Friday, I had 0 nitrites and 0 nitrates. I ran the nitrite test again and got the same result. I ran the nitrite test again on Sunday, and got .25 PPM. I re-ran it again to be safe and got 0. I ran it for a 3rd time, and got 0. The exact same thing happened Monday afternoon when I tested. So for some reason I am getting false positives on my nitrite readings. I tested my tap water and nitrite, ammonia, and nitrates were all at 0. I tried taking water from the top and middle of my tank and also got false positives.

My other question has to do with Tetra Safestart. I had read that it is okay to just pour the entire bottle into an aquarium. So I poured the entire bottle (which I later realized was enough for a 40 gallon tank) into my 15 gallon tank, after doing a water change (during which I of course added non-ammonia-binding dechlorinator). Out of curiousity, I ran the nitrite and nitrate tests hours later, not expecting to see anything. To my shock, I saw 0 nitrites (again, I had to run the test twice because I got a false positive the first time) but I saw either 40 or 80 PPM in nitrates! I ran the nitrate test twice to be sure, and ran it again this morning - I plan on doing a water change in a couple of hours because the nitrates are so high. Each time had the same result. This morning, the ammonia was half of what it was last night. Could this be because I added so much TSS? Has anyone ever seen it work this quickly? I had also added the API bacteria but I switched after seeing no results for a week and hearing about much better outcomes with TSS.
 
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There are many reasons why a test might be inaccurate. Its a home test kit not laboratory testing. It wont consistently give accurate test results, but accurate enough for the purpose you use it.

Yes i can see a bacteria supplement working very quickly, especially if you dose 3x the normal dosage. Bacteria will take down ammonia and nitrite very quickly. The issue with these products isnt whether they work on ammonia and nitrite but whether it goes on to establish on filter media or dies in the water column.
 
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