making hills

[Calqless]

I have some used reef rocks (a lot really) I was wondering how bad of an idea would it be to make small hills out of them.? Covering them in at least an 1.5 in of dirt and another 1.5 - 2 of PFS.

 

[ZxC]

They will buffer your pH to 8.2

 

[Mebbid]

Not a bad idea, it will have some buffering action in the water. My big concern is creating dead zones for pockets of gas. Typically not an issue in a tank, but there will be a lot of buildup with that much buried surface area.

 

[ZxC]

Isn't reef rock very porous with deep / small pores?

If so it could create anaerobic populations....

 

[ZxC]

Isn't reef rock very porous with deep / small pores?

If so it could create anaerobic populations....

 

[Fresh2o]

You could view anaerobic conditions as a potential method of nitrate reduction or a hydrogen sulfide source or both. Excess nitrates are not usually an issue in a planted tank.
You could use panty hose filled with lava rock. Inert, lightweight, porous, and inexpensive.

 

[Mebbid]

Second thought, the sand and dirt will eventually settle out exposing the rock.