How Quick/Soon does a DSB work to reduce nitrates?

shanghaireefer · #1 01/06/2006, 11:51 AM

My sand bed used to be about 1.5--2.0 inches deep in both my main tank and refugium. Small pebble size like the seeds of grapes. With high nitrates ,I added sugar fine white sand sourced from the virgin sands inthe Philippines adding to a total of about 4 inches in the main tank and about 5.5 inches i nthe refugium.

How soon or how quick is the DSB supposed to start working and reduce nitrates? I can see small microscopic bubbles rising from the sand to the surface of the water. I s this Nitrogen gas?

What are your experiences?

3_high_low · #2 01/06/2006, 12:49 PM

I've never been able to determine with certainty that a sand bed reduces nitrate by any measurable/significant amount. The best method to reduce nitrates IME is a water exchange. That'll work immediately, for sure.

Sindjin · #3 01/06/2006, 12:54 PM

Denitrification will also occur inside Live Rock. I run a BB and have zero Nitrates. My tank cycled in 3 weeks and since the cycle ended, my NO3 has been zero. I imagine that you should see a similar 3 to 4 week period to establish the anaerobic bacterial colonies needed for denitrification. The bubbles you see could also be air bubbles being released as the sand is settling/compacting.

What is your NO3 level? How much Live Rock do you have?
How long has the tank been established?

Dubbin1 · #4 01/06/2006, 12:56 PM

Quote:

Originally posted by shanghaireefer
My sand bed used to be about 1.5--2.0 inches deep in both my main tank and refugium. Small pebble size like the seeds of grapes. With high nitrates ,I added sugar fine white sand sourced from the virgin sands inthe Philippines adding to a total of about 4 inches in the main tank and about 5.5 inches i nthe refugium.

FYI you probably killed the sand that you had by putting that much sand on top of it if you did it all at once.