Cycle Stuck

[Gav_B_UK]

I've been cycling my tank for almost 3 weeks now using a fishless cycle.

About 14 days ago my nitrite peaked at 3.3ppm. The following day it dropped to 1.6ppm and has been stuck there ever since.

Nitrates hit 110ppm+ as the nitrite peaked. Ammonia was 0 every day prior to the nitrites hitting their peak, and are still 0ppm every day even if I raise it to 5ppm the day before.

Is my cycle stuck If so, how do I fix??

I'm not getting a brown furry type of algae appearing everywhere. I'm also getting touches of a greenish looking algae at some points on my sand. Could this be related to the cycling being stuck???

Thanks in advance

 

[anvil63]

This is just my opinion, and i've only done a fishless cycle once just to see what its like. You are obviously getting a good bit of conversion from ammonia->nitrite->nitrate as judged by your monsterous nitrate level. Therefore, I surmise that you have a good colony of bacteria established. I would stop adding ammonia, do a 75% water change, and add a few fish.

Your "being stuck" does bear some thinking as I have never seen this before. The only two things I can think off are that you're not getting enough water circulation through your filter or that the high levels of nitrate are inhibiting conversion of nitrite to nitrate.

Just some thoughts
Carl

 

[mark.w.jones]

Id say keep going. My tank took 1 week to be cycling ammonia from 5ppm to 0 in 24 hours and then a further 2 and half weeks to cycle the nitrite as well. During this time I was adding ammonia daily. My tank was a 10 gal UK (45litres) although I don't know if tank size makes any difference. Its more to do with the volume of media in you filter in combination with the flow rate through it. Give it some more time IMO

 

[Gav_B_UK]

That's why you have to love and hate forums.....

Thanks for both of you for the reply....I'm going to do a bit of both.

I am busy for the next 3 days...so that will take me to 2 1/2 weeks...got no time to do water changes due to Open Uni commitments. If there's no sign by then, I'll then look at a water change and adding a few fish by next weekend.

Thanks again

 

[Majjie]

I don't think your cycle is stuck - I think it just isn't finished yet.
I did fishless cycling on all six of my tanks and they all took different amounts of time to complete.

What you have at the moment is a full population of bacteria removing the ammonia but an insufficient number of bacteria removing the nitrite.

Don't add too much ammonia - you just need to keep those little beasties ticking over whilst the others grow. Too much ammonia and you're just building up more and more nitrite, needing a bigger and bigger population of nitrite removing bacteria to get the level down to 0.

Personally I'd do a water change as well - not least because it'll mean less changes before you can eventually add fish. Just keep trickling in that steady ammonia to keep the early guys happy