Why aren't there any nitrates in my tank?

Question

My 10 gal tank has been cycled for a few weeks now but there are no nitrates. When the nitrites went to zero the nitrates were only .5 and now there are none. Is this ok? I thought I was supposed to have nitrates? Is this harmful in any way? What role do nitrates play? I have four guppies in there right now. I dont have live plants.

Answer 1

Your nitrates could be undetectable to your test strips, if you've just done a large water change. And then, your test strips could be inaccurate.

Answer 2

You want your Ammonia, Nitrates, and Nitrites to be as low as possible (0 is great).  

Fish waste produces ammonia, which some bacteria convert into Nitrates, which are then converted into Nitrites.

If your nitrates and Nitrites are zero, you are doing great!

Answer 3

The lower the Nitrates the better for your fish. There will be some, just less than the test kit can measure. Many only start measuring at 5ppm and measure it 5,10, 15, 20 etc. So a reading of 1 or 2 is the same as zero.

The only reason you might want any nitrate in your tank is as a nutrient (source of nitrogen) for your plants. Plants seem to grow better if the Nitrate level is up around 10 or 20, and this level doesn't harm most fish.

It also means your tap water must be pretty clean, many people have 10 or 20ppm in their tap water already, so have to work hard to keep the tank level down.

Your level will go up over time once you have fish in there, but it will be easy to control the levels with partial water changes.

Ian

Answer 4

Chancesare if you are using test strips, they are not showing you nitrates registering under 20 ppm.  Get a different type of test kit or take the water to the store and have them test it.  That is the problem with these strip tests.  By the time they register in the "danger" zone it is much higher than it is showing.

If you have cycled the tank, there are nitrates it is your test kit.