Where Are The Nitrates Coming From? Help

I'm cycling a 30 gallon tank. It's cycled, but everything tested completely off the charts. So I did a 90% water change and waited a few hours to test. Ammonia at 1.0, nitrites at 2.0, BUT! Nitrates at 80! Keep in mind that my tapwater has 20ppm nitrates already. Any suggestions?

 

What test kit are you using?

 

your tank simply isn't cycled. Ammonia and nitrites need to always be 0ppm. Did you remove any filter media recently?

 

API Master Kit, and yes, I shook the #2 nitrate bottle to death.

 

Do you have results before testing - as a comparison?

 

No media change. I got an ammonia reading from 80 down to 1 yesterday after 90% water change, but nitrates extremely high at 80. I think my tank is cycled for the most part. I just think I did it starting with a large overdose of ammonia. It was off the charts before water change too.

 

The day before, ammonia over 8ppm, nitrites 5ppm, and nitrates 80ppm. After 90% water change ammonia 1ppm, nitrites 2ppm, but nitrates still 80ppm

 

So I was having the same problem with a completely well established tank, so I call an aquatic store and they told me that if you follow the instructions on the test kit you'll always get super high nitrates, so I took my water to 3 different fish stores and had them test my water and I had very low nitrates. I watched everyone test my water, and for the nitrates, they rocked the test tube back and forth like you do for the amonia one. I would take samples of your water to a few different stores and have it rechecked

 

I trusted the kit because I did tests on my established community tank first and got only 5ppm nitrates.