Fishless cycle . .am i stuck in nitirite phase?

[dianas]

I've been cycling my 120g for around 2 weeks now using a fishless cycle. I've been using seeded media (1 gallon of seeded bio-balls from an established tank) Plus I'm adding Stability. Around 4 days ago, 24 hrs after adding the ammonia, my ammonia reading is 0. My nitrites though are at least 5ppm. Nitrates vary between 10 and 20. Ph is 8.2. My filtration includes a wet/dry, and 2 Aquaclear 110's with sponges, biomedia and floss.

Is it normal for the nitrites to stay high for so long? I did a partial water change a few days ago and nitrites remained the same. Should I skip a day of adding ammonia (adding 3 drops per 10 gallons as recommended on this site) Or will the nitrite phase just work itself out? Hard to be patient!

 

[brianp]

I have seen this before when using Biospira...the ammonia immediately drops, the nitrite increases and then just won't go away. This is an indication that the second species of bacteria...the one responsible for oxidizing nitrite to nitrate has been compromised. However, you would expect an elevated nitrite reading to be accompanied by a depressed nitrate reading...but this does not appear to be true in your case. The nitrates you report could only have been generated via the oxidation of nitrite to nitrate. So, it would appear that this part of the oxidative pathway is working. It is difficult to know exactly what the root issue is, but let me suggest a few things. First, in the absence of fish, the new aquarium is a sterile environment in terms of supplying all of the metabolites required by the bacteria. These bacteria require more than just ammonia and nitrite to survive and prosper. In addition, they need amino acids and a carbon source. If I was in your situation, I would stop the ammonia, do a wc to reduce the nitrite and nitrate, add 1 heaping tsp of cane sugar (carbon source, 1x only), toss in some fish and continue to dose with Stability. The bacterial spores in Stability often form a viscous precipitate on the bottom of the bottle and some of the buffer must be removed in order to agitate vigorously enough to fully resuspend. Pour off 50% of the buffer and save....shake well and then replace the buffer. The local fish store guys tell me that Super Bac also works well.

 

[bigcol]

Ive just recently setup a 5x2x2 and filtering with an fx5, had it up and running for 1 day and put the fish straight in, they seem to be fine. I tend not to worry too much about cycling tanks now as from experience it hardly ever works unless you have fish in or using chems which i totally disagree with

 

[Yanbbrox]

Ive just recently setup a 5x2x2 and filtering with an fx5, had it up and running for 1 day and put the fish straight in, they seem to be fine. I tend not to worry too much about cycling tanks now as from experience it hardly ever works unless you have fish in or using chems which i totally disagree with

I wouldn't agree in most cases as I cycle as best I can but it's a lot easier to do with more than one tank. Used tank water, established media and gravel and a slow stocking should work out fine.

 

[rdx1555]

Whenever I've done fishless cycling I try to keep the nitrite ppm to less than 2ppm using waterchanges and reduced ammonia dosing and that seems to quicken the shift to nitrate producing bacteria to a week or less.

In the past I've let the nitrites climb to 5ppm+ and the shift took weeks also.

This is with seeded media but no Stability used.

Track your nitrates to give you an idea of cycle progress now.

 

[JakeH]

I agree. You're making Nitrate, so the BB are working. I think it would take quite a while for the nitrate producing bacteria to eat up 5ppm of nitrite. I would probably do a few WC's, then start slow stocking. You will still need to keep an eye on it, but I think real fish waste is what you're missing right now...

 

[Bderick67]

Ive just recently setup a 5x2x2 and filtering with an fx5, had it up and running for 1 day and put the fish straight in, they seem to be fine. I tend not to worry too much about cycling tanks now as from experience it hardly ever works unless you have fish in or using chems which i totally disagree with

Very sad, bad advise to be giving

Your fish "seem to be fine" yet they were/are not. You are against using chemicals, what chemicals?

 

[dianas]

Thanks all. I did a 20% wc 3 days ago. Doing another right now. ..should I do more like a 50%wc? I'm hesitant to add fish until ammonia & nitrites are at 0 though.

 

[Bderick67]

Thanks all. I did a 20% wc 3 days ago. Doing another right now. ..should I do more like a 50%wc? I'm hesitant to add fish until ammonia & nitrites are at 0 though.

Unless you have fish in the tank, doing WCs is not needed. I would not add any fish until both the ammonia and nitrite are at zero. You'll need to be paitient and keep feeding the tank with ammonia.

 

[gzeiger]

I am against using chemicals like ammonia and nitrite in my tanks...

There is an upper limit to the nitrite and ammonia concentrations that can be tolerated even by the bacteria you're trying to culture. The upper limit of 8 ppm ammonia seems to be based on solid research, but I haven't been able to find more than anecdotes regarding the upper limit for nitrite. Based on a few individuals' recommendations on other forums I'd say change water to keep it below 10 ppm, but again that number doesn't come from any solid research.

You can evaluate concentrations beyond the capacity of your kit by serial dilution, ie dilute 1 cup of tank water with 3 cups tap water, test and multiply result by 4. If it still reads at the top of the chart, dilute again until you get something you can read.

I've never heard of anyone recommending sugar, but that doesn't seem like bad advice to me as long as you change enough water to remove it before adding fish.

You say your nitrate fluctuates... does it drop when you're not changing water?