Sandbed Question

[Aries85]

So I have a quick question on something in the tank. In our sand bed there are areas that are slightly discolored and have like little air bubbles in them. The sand bed is about 2-3inches deep. These areas appear to be a yellowish color. Now I know that the sand bed has areas divide of oxygen.

Is that what these are? Should I leave them alone or when I goto clean the sand should I try to suck these spots out as well? Any info is appreciated it.

 

[Rcpilot]

I wouldn't disturb your sand bed below the top 1". Thats the part that thrives on oxygen. Below 1" or maybe 1.5"--it is low or devoid of oxygen. Thats where the anaerobic bacteria live and break down nitrates into harmless nitrogen gas, thus completing the nitrogen cycle.

I have a 5" sand bed in my tank and it's got pockets of gas all over in the lower layers. Dark brown pockets. They bubble out and "sizzle" occasionally. They come and go on their own.

Stirring the sand bed brings those anaerobic bacteria to the surface--where they will be exposed to oxygen and die. That will lead to a nitrogen spike.

Stirring the sand bed will also push upper layer aerobic bacteria down into the lower regions where there is not enough oxygen for them to survive. They will die. Bigger nitrogen spike.

At the most, I would only hover your vacuum slightly above the top of the sand bed and let it pull out loose detritus. I wouldn't actually plunge the vacuum down into the sand bed. That will only mix it up and lead to the death of bacteria and subsequent nitrate spikes.

 

[reeffreak]

Yellowish color with bubbles....is this on top of the sand bed or in it?
On top,suck it out.A pic may help us more.Could be dinoflagellate.

 

[Doc]

could also be cyano, that traps tiny air bubbles as well. I have seen purple, red and green cyano. I imagine it comes in yellow too.

I would stir it up, just the top of it, with a flick of your fingers just above the sand, it will swish the sand away and see if it comes back

-Doc

 

[Alexander]

i agree with RC. definately dont disturb your sand bed for the most part.

 

[Aries85]

I know I was not going to do anything with it, but was just wondering what it was. I am just letting it be as everything seems to be fine.