I don't know why????

[johnkristie]

I have a 210 gal with sump containing 5 gallons of bioballs and overflow chambers containing biobale. I have two T4 Velocity pumps circulating the tank. I have been cycling a tank of mine for about 2.5 weeks now using shrimp. My ammonia level rose to about 0.5 mg/L after 3 days and then dropped down to 0. However, my nitrites have risen to about 2 to 2.5 mg/L and have held steady for about a 1.5 weeks. My nitrates have risen to about 20 and have also held steady for about 1.5 weeks. Shouldn't my nitrites start to fall and my nitrates start to rise as the bacteria process them? Or am I just being impatient?

 

[reefrunner69]

Your ammonia rise and fall was pretty quick, to see the numbers for nitrates and nitrites where they are now...I'd say it could finish up the cycle any time now. I'd look for it in the next couple weeks.

 

[johnkristie]

The ammonia did drop off pretty fast. I was surprized actually. I had seeded the tank with some bacteria the day after adding the shrimp. The shrimp I put in (2) are mostly still there, although decayed. Shouldn't I be seeing a steeper rise in nitrites and nitrates??? Especially with the nitrates, without water changes they should continue to rise, right?

 

[Hara]

If you are using "virgin" bioballs, my personal experience is that they take a LONG time to grow bacteria. My predator tank took 6 weeks, with nitrites holding steady. It was not until I seeded with a couple pieces of liverock from another tank, did they drop.