Faulty test kits?

[rumblesushi]

Recently my tanks were registering a slight ammonia reading. I thought this was strange as the tanks have been running since late december, I do weekly water changes at least, I'm not overstocked and my filtration is good - eheims all the way.

So a few water changes and a few tests down the line there was still a slight ammonia reading. This seemed odd again because like I stated they are mature tanks/filters and all the fish seem fine. All hungry, active, fins spread, no fast breathing etc.

Yet when testing the tap water it registered ammonia 0.

I decided to buy another test kit, and the new one registered 0 ammonia, which I think is the true reading. The other one is wrong.

My question is though, what was it picking up that was registering as ammonia? Given that the tap water read 0.

Has anyone else experienced faulty test kits?

 

[Newt]

Yep, it was an AP test kit. I was getting a reading of 0 for iron in water that came from a well at the base of an iron mine!

I find that AP's test kits go bad faster than others do. Right now I use the Hagen Master Test Kit and I don't think I've had a faulty reading so far.

 

[rumblesushi]

Mine was AP too

 

[guppy]

I have had both pH strips and ammonia strips go bad. Usually because I had not tightly sealed the bottle they were in.

 

[RowingMunkeyCU]

so on the note of bad test kits, which test kits have worked out the best?

 

[guppy]

Tetratest laborette for me, only problem is small sample #s.