End of cycle..... no nitrates

[boosted_347]

Exactly 6 weeks into my cycle and it seems as if things are balancing out.
0 ammonia
0 nitrites
0 nitrates

I've read everywhere to do a good size water change to lower nitrates, but i'm not showing any at all. Is a water change still needed?

29g biocube, 25 pounds dry rock, fishless cycle.

Thanks in advance

[klwheat]

Did you ever have nitrates? How about ammonia/nitrites? How long have they been gone? What did you use to cycle?

[BigAl2007]

Either you have a testing error or the tank didn't cycle.

A new tank isn't able to process NO3 which is why you do the water change at the end of the cycle. Even if you used VERY high quality rock and everything you still should have elevated levels of NO3.

What did you do to "Cycle" the tank and what have your test readings been up until now?

[coralsnaked]

Either you have a testing error or the tank didn't cycle.

A new tank isn't able to process NO3 which is why you do the water change at the end of the cycle. Even if you used VERY high quality rock and everything you still should have elevated levels of NO3.

What did you do to "Cycle" the tank and what have your test readings been up until now?

Well that's not really true. Better said is a new tank is not able to efficiently process large amounts of nitrates or anything due to a low count of nitrifying bacteria.

But it is true that one should test all thru the cycle to be assured the cysle is taking place. If you did not test for ammonia in the start up phase, then did you ever acheive a start. Did you test for Nitrates and find an elevated amount > 30 and retest later and find them falling. Be aware that if you only tested one time for nitates after weeks of waiting you may have been waiting for a cycle that never started. I beleive that is what was meant by the above response. If you used dry rock there may have not been enough dead material on it to start a cycle.

Merry Skerry

[boosted_347]

Thanks for the replies. I used a shrimp and then ghost fed the tank with flake food. I had ammonia for about 3 weeks then nitrites started coming up. They were at 5.0 for another 3 weeks up until my last test which was 4 days ago. Nitrates during this time were also high, around 140. I was told that if I had high nitrites my nitrates would show high as well. I tested this morning and had no nitrites. I'd post my log, but I'm at work right now. I posted a few days ago asking about how long nitrites typically last.

[MrTuskfish]

If nitrate went from 140 to zero in a short time, with no WC; I'd suspect a bad (or mis-used) nitrate test kit. Most nitrate kits are not extremely accurate anyway; but just anaerobic bacteria taking nitrate from 140 to zero in a new tank, and almost overnight,seems almost impossible.

[boosted_347]

Ok. I'll go grab a different test kit this evening and re test for nitrates. But again.. Keep in mind for the last 3 weeks I have had high levels of nitrites. I've been testing every 4 days or so and can tell where my ammonia peaked and then my nitrites came up. So what would it mean if I still didn't have any nitrates?

[boosted_347]

Or should I take a water sample to the lfs for them to test?

[darkiss]

Is there a probe that we can stick in the water to measure nitrate?

[Pittsburgh]

Is there a probe that we can stick in the water to measure nitrate?

Yes... it doesn't come highly recommended, but one does exist. Google for "American Marine Pinpoint Nitrate Monitor"

[Pittsburgh]

Thanks for the replies. I used a shrimp and then ghost fed the tank with flake food. I had ammonia for about 3 weeks then nitrites started coming up. They were at 5.0 for another 3 weeks up until my last test which was 4 days ago. Nitrates during this time were also high, around 140. I was told that if I had high nitrites my nitrates would show high as well. I tested this morning and had no nitrites. I'd post my log, but I'm at work right now. I posted a few days ago asking about how long nitrites typically last.

Which test kit are you using? Make sure to shake the reagent bottle for the amount of time specified in the instruction. Otherwise, the test may indeed show a low incorrect concentration of nitrates. There is no way nitrates could have gone from 140 to 0 overnight. Either the first or the second test is bad.

[boosted_347]

API test kit. Like I said before.. It's been 3 or4 days since my last test. I always shake my bottles. I would get high readings but was told it is because of the high nitrites... Which has finally gone away.