Nitrate Levels in new Aquarium

[Fish Head J]

Our tank is relatively new, approximately 5 weeks old. We have been monitoring the ammonia, nitrite and nitrate levels diligently during this time. The ammonia and nitrites have stabilized quite well and are consistently measuring 0 ppm. My question is related to nitrate levels which have been reading 5.0 to 7.0 ppm for the last 3 to 5 days despite daily water changes (about 30-40% of tank). The fish all seem to be doing well so far but I wonder whether I should be concerned about this persistent nitrate level?
Am I worrying needlessly? Thank you in advance for your advise.
FHJ

 

[7Enigma]

1st a question. What test kit are you using for measuring? Is it a liquid reagent kit like the AP master test kit, or strips? The strips are known to be inaccurate. Now on to your question.

Yes, you are worrying needlessly. If your familiar with the nitrogen cycle, the ammonia is converted into nitrIte, which is then converted into nitrAte. So while you don't see any additional nitrogen from the ammonia and nitrIte, your fish ARE producing waste, but it is quickly being converted into the much less harmful nitrAte. Levels under 10ppm nitrAte are completely harmless, and many people do PWC's only when the level gets above 20, 30, or even higher.

One other thing to check is your tap water. In my case, I have between 10-20ppm nitrAte, so no matter how many water changes I do, I will always have at LEAST that much present in the tank.

 

[Fish Head J]

Thanks 7. I was feeling better after having written my question, but still wanted to ask someone with more experience.......better safe than sorry and now I know for sure. I am using a liquid kit recommended to me by another AA member.
Thanks again.
FHJ

 

[Fishyfanatic]

Agreed. Nitrates are normal and actually indicate a completed cycle. If you are using a liquid reagent kit and have been through the Ammonia and Nitrite spikes, your tank is cycled. I aim for about 10 to 20 ppm of Nitrates before water changes. Anything over 40 is dangerous.

 

[TomK2]

Don't worry about nitrate of 10. Next time you have the kit out, test your tap water, you might be surprised to find a similar amount of nitrate in the tap water.