Api Test Kit - False Positive On Ammonia?

How likely is it to get a false positive for ammonia with the API Test Kit? I'm colorblind, but I had my wife read it and she said it was closer to the 0.25 than the 0.5...but NOT 0. My tank has been running for 2 years and although about a week ago I did a major water change, I turned off the Fluval FX4 cannister filter before I did that and closed the valves to the input and output hoses. I always condition my water before putting it in so I know chlorine/chloramines didn't kill my bacteria, and the filter should be great.

Not wanting to take any chances I did a 25% water change as soon as she gave me that reading and I'll test the water again tonight after work.

I just wish there was a way to get a digital readout of the ammonia content in my water, since I'm colorblind and can never read any of the kits/strips/etc.

 

Try testing your tap for ammonia?

 

Try testing your tap for ammonia?

I'll do that, but I'm pretty sure I'd have a LOT of dead fish (5 aquariums getting weekly water changes from this tap), unless the ammonia is a new condition.

 

In the end we're hobbyists playing with little test tubes and colored liquid, not lab equipment. Most people think the liquid kits are fairly accurate, some think they're almost useless. The actual chance of a kit being off I don't know, however the way our tests are used allow for a pretty high chance of error in my opinion. If it's been up for 2 years and it's been a week since a water change and all the inhabitants are fine, I wouldn't stress about it

 

You are not the first to report false positives with the API ammonia kit.

 

How likely is it to get a false positive for ammonia with the API Test Kit? I'm colorblind, but I had my wife read it and she said it was closer to the 0.25 than the 0.5...but NOT 0. My tank has been running for 2 years and although about a week ago I did a major water change, I turned off the Fluval FX4 cannister filter before I did that and closed the valves to the input and output hoses. I always condition my water before putting it in so I know chlorine/chloramines didn't kill my bacteria, and the filter should be great.

Not wanting to take any chances I did a 25% water change as soon as she gave me that reading and I'll test the water again tonight after work.

I just wish there was a way to get a digital readout of the ammonia content in my water, since I'm colorblind and can never read any of the kits/strips/etc.

Read in another post which made great sense, the water in your tank has yet to be processed by the bacteria in your aquarium so having a small reading is normal and wouldnt alarm me. It takes some time to process vs instant change because the tank is cycled.