ID This Rock

**luke-ns** · 03-14-2013, 06:56 PM

was at the beach as im gonna start a mbuna tank and was going to add a few granite rocks but i lifted 2 rocks that look nice but im not sure what they are/ safe to use, anyone id them? Rock.jpg Rock2.jpg

**Aeonflame** · 03-15-2013, 01:23 AM

It looks igneous in nature but its composition is anyone's guess. Test it with a strong vinegar to see if there is a reaction.

**talldutchie** · 03-15-2013, 08:19 AM

For mbuna a mild to moderate reaction isn't necessarily a bad thing. These guys like their water quite hard.

**Aeonflame** · 03-15-2013, 12:45 PM

Yes, they do. I missed the mbuna part.

**CrazedMichael** · 03-17-2013, 08:04 AM

From the looks of it, the seem to be calcereous which would make the water hard. Fine for Mbuna.

**Sebastian** · 03-19-2013, 05:33 PM

The left one might actually be flint. Again, hard to tell from a picture, but flint often has this thin white layer on the outside. Inside it is gray and has sharp edges when you break it. That would be pure quartz and is therefore inert. Because it goes into an Mbuna tank it does not matter either way, if you like the looks use it!