Tropical Fish Forum

Tropical Fish Keeping Help and Advice => Fishtank Filtration and Cycling => Topic started by: bferg4 on March 25, 2015, 10:06:20 AM

Title: Cycling confusion
Post by: bferg4 on March 25, 2015, 10:06:20 AM
I'm 3 weeks into my cycle for my Rio 180. Followed the guide on here, at steps 13/14 (I think) where I continue to test 24 hours after adding the full dose of ammonia. So, 2 days ago I add my ammonia, test the following day, ammonia and nitrite still present, ammonia at 1ppm, nitrite at 2. Dose of ammonia, to 3ppm, tested around 29 hours later. 1ppm ammonia and 0 nitrite. Confused at that due to my reading the day before.

The only explanation I could think of was that the filter had not yet converted the ammonia into nitrite, or a faulty test reading. Any other info is appreciated. Thanks.

Fishless cycle btw with some live plants and pest snails.
Title: Re: Cycling confusion
Post by: Sue on March 25, 2015, 01:55:27 PM
Just to check:
You reached the stage where you had ammonia below 0.25 and nitrite below 1.0, ie stage #10, so you added a 3ppm dose of ammonia.
Next day you had ammonia 1.0 and nitrite 2.0, and you added another 3ppm dose of ammonia.
After another day, you had 1.0 ammonia and zero nitrite.
Is that correct?

At stage #10, when ammonia is below 0.25 and nitrite below 1.0, you do indeed add a 3ppm dose of ammonia.
Stage #12 says that if 24 hours after adding the ammonia the results are both zero the cycle has finished. But if they are not, as in your case with 1.0 ammonia and 2.0 nitrite, you are supposed to wait and test every 24 hours until they have dropped below the stage #10 levels again, ie 0.25 and 1.0, before adding any more ammonia.

Your next set of test results are indeed confusing. I would wait another 24 hours after that last confusing test and test again. If ammonia is then below 0.25 and the nitrite level has not done something like go up again to over 1.0, add another 3ppm dose of ammonia and see what happens after a further 24 hours.
If nitrite has gone up over 1.0 at the next test, wait until it had dropped below 1.0 before adding the ammonia.
Title: Re: Cycling confusion
Post by: bferg4 on March 26, 2015, 11:41:11 PM
Ok, didn't test the day after I had work commitments, but tested day: 0.50 ammonia and 0 nitrites. Still confused, with the ammonia dropping I'd have expected to see some nitrite.
Title: Re: Cycling confusion
Post by: Sue on March 27, 2015, 11:24:20 AM
I agree, it does seem to be a bit odd.

I think the next step is to add a 3ppm dose of ammonia and see what the results are after 24 hours.




If on that occasion you have a reading for ammonia and zero nitrite, I would dilute a sample and test for nitrite again. Mix 1 part tank water with 4 parts tap water and test that. It won't give you a terribly accurate result as that needs very sensitive measuring equipment and pure water rather than tap water but it will give an idea. The nitrite tester has been known to give a zero-like colour when it is off the top of the scale. If the diluted sample is still zero, your tank water is zero. If the diluted result is anywhere on the scale, you know your tank water is off the top of the scale.
Title: Re: Cycling confusion
Post by: bferg4 on March 27, 2015, 09:07:23 PM
Nitrates were high, but I would have expected that anyway. It's the zero nitrite reading that is confusing.
Title: Re: Cycling confusion
Post by: Sue on March 27, 2015, 09:36:14 PM
If your nitrate is a lot higher than the tap water level, it has to be coming from nitrite so you do have a good number of nitrite eaters.

Adding that dose of ammonia then testing again after 24 hours should provide some interesting results  :)
But it is a known quirk of nitrite testers that a high level can give the zero colour, which is why I suggested testing a diluted sample if nitrite is zero again with a non-zero reading of ammonia.
Title: Re: Cycling confusion
Post by: bferg4 on April 05, 2015, 07:16:36 PM
I'm still getting these same odd readings. 2 days ago added 4ppm ammonia (miscalculation on my part for that one). Tested 24 hours later: 2ppm ammonia and 0.25 nitrite. Didn't add any more ammonia, was unable to test the following day due to being away with work. Home today and tested: ammonia - 0.50ppm and 0 nitrite.  :o
Title: Re: Cycling confusion
Post by: Sue on April 05, 2015, 08:52:59 PM
I would work on getting your ammonia to drop from 3ppm to zero in 24 hours. In other words go from stage #10, adding 1ppm or 3ppm depending on the ammonia reading, until you achieve that zero ammonia. Ignore your nitrite for now.

Once you reach that target, look at your nitrite and if it is zero do a dilution test as well. And maybe even get nitrite tested at a shop just in case there is something wrong with your tester. if they agree that nitrite is zero, consider the cycle finished.
Title: Re: Cycling confusion
Post by: bferg4 on April 07, 2015, 07:07:22 PM
Thanks Sue I'll do that. Info much appreciated as always. :)