Cycling Problems - Its All Gone Fubar

[JMcQueen]

I've been cycling a tank for about three months now and all seemed to be progessing normally but everything seems to have collapsed. It had been processing ammonia in 12 hours and nitrite in 24 and I was just waiting on the nitrite processing to fall to 12 hours. Now, its not even processing ammonia in 24 hours.

The only things I can think of is if the filter has been turned off or untreated water introduced but this doesnt appear to have happened (or if it has nobody is admitting it).

It seems I've got not choice other than to do a 100% water change and start again and hope that some of the bacteria may have survived to speed things up again but its so demoralising after three months to look like I may need to start again. Does anyone have any ideas as to what may have caused this?

Temperature has been maintained at 29oC

 

[Mo1959]

Have you checked your PH. My water is extremely soft and my ph constantly crashed to 6 or less which stalled the cycle. Like you I had been persevering for over two months and not really making progress.

If this happens to be the case, a little crushed coral added to your filter will help bring it back up.

 

[JMcQueen]

I live in a hardwater area so its unlikely but its also not possible to test at the moment due to the ammonia still in the water.

 

[waterdrop]

Hi JMQ, You make it sound as if you are away from the cycling process (is it a fishless cycle or a fish-in cycle?) and someone else has charge of the tank for periods of time?

So I looked back at your threads (numerous!) to try and get a picture but you had so many different things going on I could't put it all together. It seemed like you'd had a small tank but then switched to a larger one when you figured out that two black moors needed a larger tank perhaps and then you did introduce these after a fishless cycle (and there was a log) but that the nitrate stayed sky-high in that tank despite the large water change when introducing the goldfish. I also seem to remember you had traces of ammonia and nitrite as well as considerable nitrate in your tap water? (is that right?)

Anyway, let us know if you're now off on a new tank or re-doing one of the previous. We'd assume you have mature media from your previous efforts?

~~waterdrop~~

 

[JMcQueen]

Hi JMQ, You make it sound as if you are away from the cycling process (is it a fishless cycle or a fish-in cycle?) and someone else has charge of the tank for periods of time?

So I looked back at your threads (numerous!) to try and get a picture but you had so many different things going on I could't put it all together. It seemed like you'd had a small tank but then switched to a larger one when you figured out that two black moors needed a larger tank perhaps and then you did introduce these after a fishless cycle (and there was a log) but that the nitrate stayed sky-high in that tank despite the large water change when introducing the goldfish. I also seem to remember you had traces of ammonia and nitrite as well as considerable nitrate in your tap water? (is that right?)

Anyway, let us know if you're now off on a new tank or re-doing one of the previous. We'd assume you have mature media from your previous efforts?

~~waterdrop~~

Hi WD. Unfortunately the blackmoors died so I gave the small tank to my parents so that they could put a single common in it. I then started work on a 120L tanks. Nobody has been looking after the tank as such but there is always the possibility that my other half could have accidently turned the filter off for a day or so whilst I was working away but I wouldnt have thought that would have damaged things so badly.

The tap water is zero for ammonia and nitrite but 30ppm for nitrate.

 

[waterdrop]

I don't understand your statement that its not possible to test pH when there's ammonia in the water. pH is one of the standard daily tests (although when it seems stable we sometimes skip a day or two before doing it again) we all do to our fishless cycling tanks and there's certainly ammonia in there when we do it. WD

 

[JMcQueen]

Sorry, what I meant to say was that whilst I can test the PH, wont it be skewed by the ammonia that I've added rather than a true reflection of the PH of the water. My thinking was that a PH test would be of most value immediately before ammonia was added so that you can see the PH of the water once its processed the previous days ammonia?

 

[waterdrop]

Well its true that ammonia is a base but in the parts per million that we're dealing with I don't think its really an issue since we are just keeping a crude daily every other day check or so on whether our pH has suddenly decided to make quick movements in the acid direction.

The problem with the high nitrite levels having a little nitric acid component and pushing the acidity is that the autotrophs will quickly slow down their reproduction process if they detect quick movements. I don't think it matters that much whether the overall pH of the water is high or low, its the rapidity of pH -change- that they respond to and don't like. Doing daily KH tests (I'm not recommending you do this, its just something I've done and can describe) lets you see a smooth drop in carbonate hardness that can eventually cause quite a rapid little downtick in pH. I think its those downticks in pH that the N-Bacs really take as a (I'm probably exaggerating here for story purposes) warning sign and slow down their development.

WD

 

[JMcQueen]

Just checked my PH and it had crashed to 3. Though Im not sure if thats due to a problem elsewhere or a build up of ammonia. My ammonia kit ran out about 4 days ago and because it was dealing with the load in 12 hours, I just kept redosing every 24 hours until I can get another kit (tomorrow).

Guess thats what happens when you take your eye of the ball.

Anyway, I've done a 99.9% water change and redosed the ammonia so will have to see how badly things were affected.

 

[Harlequins]

You could've added bicarb of soda to bring your ph back up ...

I hope things get back on track

 

[waterdrop]

Good. Now that you've found the problem, it'll be easy to deal with. WD