Fishless cycle in progress but nitrites not going down?

[Siouxish]

I've been doing a fishless cycle for about a 1 1/2 months now and the ammonia has been zero for about three weeks now. The nitrites are very high and haven't started to drop at all. Also, no nitrates to speak of either. Any ideas to speed up nitrifying process? Unfortunately I don't have an established tank to get anything from to help.

 

[Blinky]

Can you post some details on exactly how you've been doing your fishless cycle (amounts of NH3 added, whether you're using pure NH3 or something like fish food/other protein to create ammonia) and the levels of ammonia/nitrite in the tank day to day throughout the cycle so far, as well as what type of filter, media, and any maintenance you've done?
All that information will give some insight into why your cycling isn't working and make it easier to come up with the solution.

 

[Siouxish]

I'm using pure ammonia and was keeping it at 4-5ppm until the Nitrite started showing up. Now I am putting in enough to spike it to 1 ppm within and hour of inserting, then the ammonia drops to almost zero within 24 hrs, and I repeat adding some more ammonia. The nitrites seem to stay the same no matter how much ammonia has been cycled.

I've got a Fluval 204 and a Eclipse Bio Wheel filtering the 50 gallon tank.

 

[OrionGirl]

pH and KH?

 

[bobbi619]

Having the same problem here. I really thought it would go alot faster once Nitrites started to rise.

Its been a week since Nitrites showed up, now they are at 5-6 ppm, I keep adding Ammonia daily to bring it to 1-2 ppm Nitrates are fluctuating between 5-10. Running a Top Fin 60 Whisper filter.

pH is 7.8/kH is 89.5

I know one of these days I will check Nitrites and they will be 0, but I really did think it would have happened already, I did have my other tank to rob from.

Patience Patience Patience :thud:

 

[Siouxish]

Turns out my PH had dropped to 6.0. What would have caused it to drop that low? I have no live plants and the tap water is about 7.8. I've changed out 80% of the water and inserted some more ammonia. Any other suggestions?

 

[Blinky]

Ah HAH!
From what I've heard, very low pH can prevent the development of nitrifying bacteria - I think you stumbled on your answer here!
As for why the pH dropped, my guess is your water is very soft. Can you test your KH? It may not have a very good buffering capacity, and in that case pH can really bounce around (I'm not sure of all the chemistry involved, but I know that when CO2 increses and O2 decreases, pH can nosedive if your KH isn't high enough to buffer the pH)
If you find that your KH is low, you can buffer the water in many ways. I'm using sodium bicarbonate (baking soda) to buffer my tank, you can also use crushed coral in the filter or certain rocks as decoration that will leach calcium gradually into the water and increase KH.
You can buy kits that test hardness, (Tetra makes one that tests General and Carbonate hardness - GH and KH) or have a test done on your water at your LFS.

 

[livewyr25]

THe same thing happened with the ph with me between today and yesterday. last night i tested with a ph of around 8.2, and today it was between 7.2-7.4. i too am doing a fishless cycle and am making it a cichlid tank, and i have a cichlid substrate to buffer and raise the ph. dont know why it dropped like it did, since i already have the buffering capability from the substrate.

 

[livewyr25]

i forgot to include that my tank is completely cycled with ammonia at 0, and nitrites at 0. just waiting for my rocks to be shipped before i add any fish. so im adding ammonia to the tank every day to ensure the bacteria doesnt die.

 

[RTR]

Fishless is the equivalent of a very heavy bioload. Normal nitrification is an acid-generating process, so it burns up KH, allowing the pH to fall. When doing fishless, you need to know what the water's KH is, and if the pH starts slipping, you should water change to restore the KH and protect the bacteria. A pH crash can be damaging to the new bacterial colonies - at and below pH 6 they are not growing and may be dying.