live rock set on sand or on glass?

[jimreemts]

I moved my tank, when I set the live rock back in I set it ontop of the sand bed. I was told this is wrong i should set the rock on the glass and push the sand around the rock. The reason was the sand under the rock compresses and becomes anarobic creating a area of toxins within the sand. Has anyone heard of this before?

 

[rcoultas]

you will always have anaerobic areas in the substrate and they can be very beneficial - anaerobic bacteria colonies can perform the final step in the nitrification process ( converting nitrates into nitrogen gas) what you do not want are "dead" areas where there is little or no water movement - this will cause an accumulation of detrius and other wastes thus causing excess nitrates. HTH

 

[dogstar]

Many feel its best to place the rocks directly on the glass so that later, if you have any animals that dig or shift or bury, that they want undermine the rocks and cause them to become unstable and fall, perhaps trapping or killing the animals or breaking corals or glass.

 

[earlybird]

Some place eggcrate in first and then put the rock on that and finally the sand. The eggcrate sucures the rock very well.

 

[addicted2]

I put eggcrate down first then some base rock..then my live rock. the sand goes all around the baserock and that has created some really great caves and caverns for my gobies etc...looks nice too..that way..any tunneling goes on and all the rock stays in place

 

[dogstar]

Originally Posted by earlybird
Some place eggcrate in first and then put the rock on that and finally the sand. The eggcrate sucures the rock very well.
Agreed, thats what I did as well.

Not only does this prevent the rocks from moveing downwards as would placeing them on the glass do, it also keeps them from slideing sideways which is still possible even if place on glass....