Tank cycling question.

[Terry Adamson]

Hello,

I am not new to keeping a marine tank nor am I new to cycling a tank but this is staring to bug me slightly.

I am currently 2 weeks into cycling my 6x2.5x2 tank and I'm using the same method I normally use chucking a shrimp in the sump and let it do it a thing. I've been checking ammonia readings every other day with my salifert kit and I've always had 0 reading and because of this I've thrown some mysis in 4 cubes in total over the 2 weeks and another shrimp but no ammonia reading still. Today I've checked nitrite for the first time and I'm getting a reading of between 1 and 2. I hadn't bothered checking before as I was waiting for ammonia to show first.
I've used live sand and the rock was dried for about 3 weeks before it went into the tank.

Can anybody shed some light on what's going on because I've never seen this happen before.

Thanks.

 

[Big G]

Welcome to R2R! Two things: the live sand must be "very" alive; the drying of the rock wasn't too hard on the bacteria, especially deep within the rock. Sounds like a good thing. Might want to dose some "clean" ammonia (1-2 drops per gallon usually works to get 1-2 ppm) and check it 24 hours later for consumption.

 

[Terry Adamson]

Thanks for the welcome. I still have 4 king prawns in the tank, do you think I should leave them in for a few more days?

 

[Big G]

Think I'd run the "clean" ammonia test; pull the prawns. The clean ammonia is commonly available at Ace Hardware as Janitorial grade. There are no additives. That's what you want. This way you can measure the ammonia consumption rate and know if the correct bacteria are in fact there and working.

 

[Terry Adamson]

Thanks. Yeah I've been looking for a couple of days for some ammonia that has nothing else in it and I can only find it online (im in the UK.)

I've just done a nitrate test and it is showing maybe 100 (salifert). I'm thinking maybe the ammonia spike happend early on and I missed it and the bacteria dealt with it quickly.

 

[jda]

Any bacteria that you had on the rock could be dealing with the dead organics on the rock that are in closer proximity. In close proximity, ammonia to nitrite to nitrate all without getting much in the water column.

If you have not cycled a tank before with dry/dead rock, then it is different... it can take a long time for the dead organics to get eaten out of the rock, especially as they get deeper.