Hi Steve,

Those bubbles are nitrogen gas. As they rise and pop, the
are removing nitrates from your system. It is good thing
to observe, and these bubbles forming near the upper 1" of
substrate is quite common.

Marc


SA wrote:

Hi all,

In my sand bed I see little air bubbles approximately 1/4 to 1/2 half inch
deep from the surface of the sand on the glass. Is that de-nitrification
going on? I thought that this occurs deeper in the sand bed?

I have about 3-4 inches of sand on my tank and was hoping to benefit from
anaerobic activity, however right now I am not sure as to what those bubbles
are. Trapped air... or actually nitrogen.

Any ideas?

TIA

Steve



--
Personal Page:
http://www.sparklingfloorservice.com/oanda/index.html
Business Page: http://www.sparklingfloorservice.com
Marine Hobbyist: http://www.melevsreef.com