Cement Live Rock

[newland]

Hi All

I'm going to experiment with making some Cement Live Rock. Which will probably just be rock but at least it should be a pretty rock.

I know it will take a long time before it ready for the tank due to PH levels.

Has anyone tried it?

I'm also thinking about making a background for my 2ft tank. Nice little thing that will have caves in it etc.

 

[Navarre]

I have made some liverock (man made liverock) in my tank. you need cement, aragonite sand and rocksalt. Mix the cement with the sand (cant remember the ratio now sorry) and also add the rock salt when the mix is complete. pour the mix into a box of sand that has a shape moulded out of it. once the rock is set, add the new rock to a barrel of freshwater. eventually the rocksalt inside will dissovle leavning holes and fissures etc. keep changing the water in the barrel and over a period of weeks you will notice the PH will finally drop to acceptable levels. Once the PH reaches 8.0 - 8.4 then remove the rock and put in a salt water envrionment and leave for a further week. check ph levels again and if they have not risen then you can add to a marine tank.

Hope this helps.

 

[newland]

Thats what i was going to try.

Great idea about the rock salt.
Someone recommended pasta.

I was also thinking about spagatie as this would create lots of long thin holes.

Think its a good idea?
Now i've just got to find somewhere to get aragonite sand from in the UK

 

[leon]

i also heard of putting the piece of rock into a toilet cistern, the water flowing over all the time, and having new water helps alot more! Ingenious i thought!.
Will the cement not have any affect on the water?, or leech anything into it?, i thought of having a tank with brick and cement and having a glass front, but thoght the cement wouldnt be any good for the tank!
leon

 

[Navarre]

The cement wont leach anthing once its cured. the problem is the huge PH spike you will get. the ph can rise well over 12 or 13 so it needs constant water changes until it finally drops (takes about 8 weeks)

 

[newland]

Cheers for all the help.

The toilet idea is a good one. I'll prehaps give that one a go for about 5 weeks then transfer to a bucket and start testing PH.

Thank you to everyone who helped me.

 

[sammydee]

I read that rocksalt is not a good idea because it stops the cement curing so strongly and greatly weakens the rock.

 

[Navarre]

never heard of that one. could be true i guess as i am not chemist and have no idea if this would cause a reaction as such. All rock made in this way that i have seen though seems to be fine.

 

[chkltcow]

Another one I've heard is plastic shavings, like what you'd get from cutting plexiglass with a tablesaw or something. Just think about how quickly coraline grows on the plastic bits in your tank... filter intakes, powerheads, etc. The plastic is supposed to help the coraline grab a foothold quickly and spread on the manmade live rock.

 

[Navarre]

yes i have heard this too. However it would still need something in the mix that will dissolve during curing to help make it porous.