A Halted Fishless Cycle?

[NewFeesh]

I started fishless cycling my tank 12 days ago. From 5 ppm, the ammonia level dropped to 2 ppm in a week--where it's been lingering since then.

For the past 5 days, the ammonia has been stuck firmly at 2 ppm. Shouldn't it be following the earlier curve? What would make it stop?

Tank setup:
10 gallons (US)
2 Anubias, 1 wisteria, 1 Java fern (plants)
mixed sand and gravel substrate
Aquaclear 150 filter
Temp set at 84 degrees F
Piece of driftwood (currently covered in mold that's slowly disappearing)
20 watts of fluorescent light (10 hours/day)

Stats:
Ammonia at 2 ppm
Nitrites and Nitrates at 0
pH at 8.5

Thanks for your help!

 

[Harlequins]

Sounds pretty normal to me for early stages of a fishless cycle,give it time,patience is a virtue

The ammonia will go down in time,and nitrite will eventually start showing

 

[NewFeesh]

Oh. Why would it drop so nice and quickly to begin with and then just stop? Did my bacteria get overwhelmed?

 

[Gvilleguy]

You are not the first person I've seen post that kind of result this week. I'm not sure what would cause the quick drop and then apparent "stall", especially since your pH has not crashed.

 

[waterdrop]

12 days is nothing.. very common for nothing to happen in the first two weeks - the chances get better that a small number of A-Bacs will make their presence more apparent during the third week but sometimes it even goes on through that third week. It doesn't matter much, as when they finally kick in they will rapidly begin reducing 5ppm to zero ppm within a day and they will usually do it day in, day out all through the second phase (and they will produce way too much nitrite(NO2) for the N-Bacs to handle) and then finally in the third phase they will decide to mess up and -not- reduce the ammonia all the way to zero, much to your surprise and displeasure. They are troublesome little beasts and they do not like to give out smooth curves on graphs all that often.

~~waterdrop~~

 

[NewFeesh]

I read in a Tips and Tricks for quick cycling that the bacteria may need micronutrients in order to divide at their fastest. As a biochem major, I could see this. It may simply take them longer to up the colony numbers if they can't grow as quickly. The site recommended adding a tiny crushed pinch of fish food for the extra nutrients (phosphorus, for example).

At any rate, (because of in spite of my fish-food adding), tonight I got 0 ppm ammonia reading!!! So glad the stall is un-stalled.

 

[waterdrop]

Yes, I agree with what you heard. Some of the most common micronutrients known to help autotrophic bacteria are the Calcium and Magnesium supplied by common tap water (which usually has plenty of these as far as the bacteria's needs are concerned.) As for other things like phosphorus, you are indeed correct that a tiny pinch of food would help this or a tiny dose of typical plant foods, especially the Trace or Iron products that are sometimes used by plant enthusiasts alongside macronutrient feedings.

The need for these things is so minor however that I believe the feeling is that its a pretty rare problem that these would be showstoppers for many people.

~~waterdrop~~