Live Rock made from concrete moulds?

[travis_]

I was checking out this website http://www.smooth-on.com/gallery.php?galleryid=375&cPath=1235 showing how the tiniest of detail can be captured using latex moulds and concrete. I would think this same process could work for live rock, get some interesting shaped real pieces and make moulds, ideally creating an end result that can not be differentiated from the real live rock once it gets some coralline growing on it. However, it does seem like a lot of work to create the mould. I was also thinking about adding some inert lightweight material to lighten the weight of the finished product, perhaps add a bunch of those little Styrofoam beads?

 

[Myteemouse]

only problem with concrete rock is it take a long time to get the PH down!

 

[returnofsid]

If you make small pieces, put them in the tank of your toilet. That way they're always getting flushed with fresh water. It'll help cure them faster and lower the pH. It'll still take a coupla months. Large pieces will take LOTS and LOTS of freshwater rinses and can take up to 6 months to cure and for the pH to lower. There's lots of great links for DIY concrete "live" rock. Easiest is to make it in a kids swimming pool filled with sand. Just dig out areas for your mold, coat them in rock salt. The rock salt helps give it a nice, porous look and the salt dissolves when you're rinsing the rock.

 

[sgwill122]

I have seen folks use rock salt, pasta noodles and even rice crispies to lighten the rock and add texture. Never read anything about trying styrofoam beeds, you might have a problem with the surface beads coming free over time and floating around the tank. Would be interesting to try.

One of the biggest problems with making the rock(besides the work involved) is cure time, the lime in the concrete leaches out causing a significant PH spike. I have read it is on the order of months being submerged before you can put it in your tank and not negatively impact PH.

 

[Myteemouse]

If you live by a river or have someone that has a stream going threw there yard you can "CURE" it faster also.

 

[returnofsid]

Very true...except then you might load it up with nitrates, phosphates or who knows what else...But it'd cure much faster. Then you could bleach it to clean it up.

 

[Myteemouse]

exactly!
That would be just to get the PH down then clean/bleach then cure it