Odd ammonia test results

I accidentally started my 10 gallon tank through a minI cycle a couple weeks back, so I've been doing daily ammonia tests on it using the API liquid test. Recently I noticed that if I run the test once it still shows ammonia at anywhere between .25 and 1.0 ppm, but if I rinse the test tube and test again immediately after I'll get a reading of 0 ppm. The only difference between the tests is a SLIGHT amount of residual tap water in the 2nd test from when I rinse out the tube. I just got a reading of nitrites of maybe .5 ppm and nitrates around 20-40 ppm. Doesn't help I'm not great with subtle color differences *sigh* Anyway, I've also been using Seachem AmGuard on the tank to make life easier on my fish. All of them look fine, but I did lose 1 (literally) about 1-2 weeks ago. Side note: I also just ran an ammonia test on a fully cycled tank and got a reading of 0 right off the bat.
Any thoughts on what test result I should actually believe? I'm inclined to say the 0 result because it's been 3-4 weeks of daily to every other day water changes, I'm getting nitrates, and my fish seem fine. I don't want to take chance though.

 

We did the API ammonia test to death in another thread some time ago. It is quite possible to get a reading of .25 ammonia even when it is zero. API cover that by saying that the test is accurate to +/- .25.
Just keep checking but it appears from the nitrate reading that the tank is cycled. It is probable that the test is picking up ammonium from your tank water which isn't present in your tap water.

 

If you are still seeing nitrites the cycle isn't quite done yet. It seems you aren't the only one seeing .25 consistently but I would err on the side of caution and keep up with the water changes until you consistently see 0 ammonia and 0 nitrites.

 

I'll probably just keep watching the tank and doing water changes if I see above .25 ammonia. Which is about what I've been doing honestly, but it's always nice to have another opinion, so thank you Think I should keep up with the AmGuard for now? As far as I know it doesn't hurt anything to keep using it, so I may as well right? Btw I've got endlers, a guppy, a couple rilI shrimp culls, and assassin snails so not the most sensitive lot fortunately.

 

I'll probably just keep watching the tank and doing water changes if I see above .25 ammonia. Which is about what I've been doing honestly, but it's always nice to have another opinion, so thank you Think I should keep up with the AmGuard for now? As far as I know it doesn't hurt anything to keep using it, so I may as well right? Btw I've got endlers, a guppy, a couple rilI shrimp culls, and assassin snails so not the most sensitive lot fortunately.

You are very welcome I have never used AmGuard so really can't comment on it. I both use and normally recommend Prime but if what you are using is working I can see no need to change at this point.

 

So I did my water test earlier and got 0 on the ammonia. I'm starting to think this is gonna be a "take your car to the mechanic and it suddenly stops making noises" style moment. There has got to be a better way to say that, but hopefully you know what I mean ;P
Anyway, just wanted to share that because my currently sleep deprived self found it mildly ammusing. Thank you again for the advice, and wish me luck with keeping this tank stable.

 

We've switched to Tetra ammonia test strips for regular testing. As long as no colour develops you know you're at zero. If there is a colour change then it's time to wheel out the liquid test!

 

So I did my water test earlier and got 0 on the ammonia. I'm starting to think this is gonna be a "take your car to the mechanic and it suddenly stops making noises" style moment. There has got to be a better way to say that, but hopefully you know what I mean ;P
Anyway, just wanted to share that because my currently sleep deprived self found it mildly ammusing. Thank you again for the advice, and wish me luck with keeping this tank stable.

Zero ammonia is good. What about the nitrites. Have they gone down to zero yet?

 

I think I jinxed myself because the ammonia is back to reading .25ppm again -_- No nitrites though, and nitrates are around 20ppm. I'm starting to think the tank's cycled and I'm getting false positives. I'll still keep an eye on it for a while though and do a water change if ammonia ever reads above .25ppm

 

I think you are right. I am wondering if it is at all possible the AmGaurd is giving you these what we hope are false positives for ammonia. I think you are good to go since you are not seeing any nitrites and are seeing nitrates.