Dry Rock Suppliers

[Reefer Rob]

The type of rock makes all the difference. You want a nice light, porous rock. Heavy, dense rock, whether it's live or dry is useless, and will just lead to frustration with your nutrient levels.

[FitoPharmer]

Originally Posted by Reefer Rob

The type of rock makes all the difference. You want a nice light, porous rock. Heavy, dense rock, whether it's live or dry is useless, and will just lead to frustration with your nutrient levels.

That is not 100% true. Rock that is too porous can be also problematic. Dense rock has the anoxic areas that harbor the bacteria that convert no3 into nitrogen gas.

[Reefer Rob]

Originally Posted by FitoPharmer

That is not 100% true. Rock that is too porous can be also problematic. Dense rock has the anoxic areas that harbor the bacteria that convert no3 into nitrogen gas.

I mean the structure of the rock itself, not that it necessarily has more passageways etc... though this is important as well IMO. Water needs to be able to penetrate the rock in order for it to function well.

[FitoPharmer]

Originally Posted by Reefer Rob

Water needs to be able to penetrate the rock in order for it to function well.

That has little to nothing to do with what makes live rock function.

[Reefgoat]

Originally Posted by FitoPharmer

That has little to nothing to do with what makes live rock function.

Interesting, please explain.

[FitoPharmer]

Tonga Branch



Porous Rock

Tonga branch as far as I know is some of the densest LR available on the market. My one tank had a majority of Tonga branch. Everyone said the tank looks like it did not have 1 pound per gallon, but some of the larger pieces were around 40Lbs! A 40 pound Fiji LR would be 3-4X the size.
Most tanks do not need more surface area for the bacteria that convert NH3 or no2. They process it quite well, and you do not even need LR for this. Bio balls even work for that process. There is then just a build up of NO3 left. The only thing that can remove NO3 I know of from a reef aqaurium is anoxic zones in LR. However if the rock is too porous and there is too much water flow through the rock these zones cannot establish due to the higher oxygen levels.

Personally I have never found the porosity of LR to effect the biological filtration. However I could see porous rock acting as a much better mechanical filter.

[Reefer Rob]

So you're saying the de-nitrification is taking place on the surface of the rock? I've never heard of this, I always thought the anoxic zones where inside the rock. Can you point us to references for this, you've got me very curious.