Strange cycle?

[EddieKay]

I just filled a 75gal. reef tank with 100lbs. of partial cured rock 2 days ago. I scrubed off all slimey and decaying pieces then placed it in the tank.(new tank, no life forms). Before I placed the rock I tested the water. Nitrites and nitrates were zero as expected. Today, 2 days after rock was put in I tested again, Ammonia was 0.25 mg/l, nitrites were 4mg/l, and nitrates were 100mg/l(all salifert tests). Is this normal cycling, why is ammonia so low and the nitrates so high already(i understand the nitrite part). Also should I do a water change today, If so how much

 

[Anonymous]

I just filled a 75gal. reef tank with 100lbs. of partial cured rock 2 days ago. I scrubed off all slimey and decaying pieces then placed it in the tank.(new tank, no life forms). Before I placed the rock I tested the water. Nitrites and nitrates were zero as expected. Today, 2 days after rock was put in I tested again, Ammonia was 0.25 mg/l, nitrites were 4mg/l, and nitrates were 100mg/l(all salifert tests). Is this normal cycling, why is ammonia so low and the nitrates so high already(i understand the nitrite part). Also should I do a water change today, If so how much

Hi and welcome Eddie, you may want to start a new thread with these questions so it gets more notice. How old are your test kits, if you have doubts about them retest at your LFS or use new reagents.

IME I think that the values you are seeing are a bit on the high side but if the rock was partially cured you could see an early nitrite to nitrate spike as there were existing nitrosomas bacteria in the rock. You do understand how the cycling process works, right? Simply put that there are several types of bacteria, and as those colonies grow the water values change.

Quickly: Ammonia (very toxic from decaying organic matter) is converted by the good bacteria into Nitrite (which is slightly less toxic but still bad juju).

Other good bacteria take over and convert the Nitrite to Nitrate which is the least toxic part of the whole process which can be diluted and exported from the tank (to a point) by water changes. Until those colonies of bacteria build up to process the loads your values are going to pop high like that.

To answer your other question yes if it was my tank I'd do a 30% or better water change and retest tomorrow.

 

[ChrisRD]

Oops - split this out of another thread before noticing the poster already started a new one...

http://www.reefs.org/phpBB2/viewtopic.php?t=63520