concrete cow-pies (DIY live rock)

Okay I have about 350 lbs of concrete rock that is about 5 years old. It is in my 210g display. The mix I used is 2 parts crushed oyster shell, 2 parts Southdown sand and 1 part portland I/II cement. I am not having any problems.

 

mushrooms and cow pies.boy Im gettin old

 

I don't see any SPS... I say that because the prior post regarding Oyster Shells he referenced bound PO4 becoming free and affecting SPS. I don't know that it's true, just wondering. But I have read where oyster shell is used to adsorb PO4. So if thats true, then I supposed it wan release it as well...? I personllay don't like the look of the oyster shell, or the GARF recipe at all... But to each his own. Your tank looks nice though, and basically once you have coral on it, who really pays attentionto the rock anyway?

 

I can see how it is hard to see any sps, the tank. I had a problem with a RO/Di system and had a pretty bad out break of HA. The tank was redone in November '08. These are some of the current sps residents. Beware a couple look week they were not under the best lights during the move.

 

So do you attribute the rock to the HA outbreak, or the causal nutrients?

 

It was not the rock or I would be facing the same problem today.