# High nitrite and nitrate levels.



## MamaBookworm (Jul 30, 2015)

Hi
I've kept freshwater tropical fish for nigh on 15 years, so don't regard myself as a newbie but I am totally baffled by my latest water readings.
I have a 75L community tank that took nearly 4 weeks to cycle and has been up and running for 3 months (post cycling). No fish were introduced during the cycling process. The fish seem very healthy (I have fry from both mollies and platys) and are feeding well. 
Yesterday, I did my weekly water check and was expecting to carry out the usual 10% water change. However, I found the ph to be fine, amonia 0, but my nitrite level at 1.6 and the nitrate at between 20-50! The previous reading had been 0 for both. I did a 20% water change and re-tested today, with the same results. 
I haven't added any new fish for over a month. I have never been successful with live plants so there are only plastic plants in the tank. The water is crystal clear (I know this isn't necessarily a sign of good water quality) and have no visible algae. 
My local water tends to have high levels of nitrates, but since the cycling process was complete this hasn't been a problem.I'm worried about my fish - any advice gratefully recieved.


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## Watermelons (Jul 21, 2015)

Sounds like the tank didn't cycle properly.

You have to remember too, the moment you add fish, the tank re-cycles.
When you first start a fish-less cycle, the BB that grow are grown for whatever "ammonia source" you added to the tank, which is usually much less then fish put out, especially if you added a few fish all at once. So the tank in a sense has to re-cycle itself to catch up to the waste from all the fish that have been added.
But since you see 0 ammonia I would say this new cycle is well on its way. A larger water change would be beneficial. Keep an eye on your perams for the next while and see how they go, doing a water change when they get into the danger zone.


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## MamaBookworm (Jul 30, 2015)

Thanks for your advice. I am just baffled why they should spike when I haven't added any new fish for 4 and a half weeks and up until yesterday water quality was perfect. Will do a larger water change today and hopefully it will calm things down. Thanks again for your reply.


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## Watermelons (Jul 21, 2015)

If you've been testing the entire time then its hard to say. Those levels seem consistent with nearing the end of another cycle, but then you would have seen ammonia levels like 2 weeks ago. 
A fully cycled tank should only yield nitrate readings.
When did the babies show up?
Have you been increasing the amount of food since they were born?


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## MamaBookworm (Jul 30, 2015)

Noticed the babies about 2 weeks ago. I have seen 5 swimming around. As they are still quite small I haven't increased the amount of food yet. 
If I had seen an ammonia spike a couple of weeks ago I could understand the spike in nitrates and nitrites, but there wasn't one. I have never had readings like it in all my years of fish keeping.


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