# Lava Rock



## romerx (Aug 30, 2009)

I went to a local pond/water garden store close to me to find some decor. They have about 15 pieces of lava rock the size of a beach balls. Has anyone tried to break it apart. Don't know if it will just crumble or break in large chunks. They want $10-$15 dollars per rock. I got hooked on the hobby & have only Red Zebras & a few ob's but I am adding additional tanks to have different species from lake Malawi & Tanganyika. Is this a good rock to use


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## Electrophyste (Aug 5, 2009)

i think its great used it for africains, couldnt tell you how well it breaks i never tride but would assume it would crumble. but 15 for a beachball size piece is really decent i paid over 50$ canadian for enough to fill a 20gallon in small chunks


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## PfunMo (Jul 30, 2009)

I don't know how you are equipted so this might not fit you. If you have a skil-saw it might pay to buy an abrasive blade made for cutting concrete. Even though you can't reach all the way through a beachball, it will give the rock a definite place to break rather than random. Once you have the score line made with the saw, use a chisel and using a rather light touch, go around the score line until the rock cracks open. Use a gentle jarring rather than brute force. Like cracking eggs but a bit rougher. 

Extra note of caution . When cutting masonry, it pays to lay a wet rag over the cooling vents on the saw. Rock dust eats the bearings if it gets much inside.


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## romerx (Aug 30, 2009)

i actually have a gas concrete saw so that might work better. thanks for the information


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## Wolffishin (Sep 9, 2009)

In my experience lava rock breaks with very sharp edges but you can use a Dremel to grind them down.


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## cjacob316 (Dec 4, 2008)

use a good rock hammer


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## thebigman65 (Jan 3, 2008)

Hammer and a concrete/masonry chisel the kind with the hand protector. It works great and the lava rock will not cumble. Then you can grind sharp edges as noted above.


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## Ed_209 (Dec 22, 2004)

I had some lava that size too. I used some dollar store masonry bits to drill dozens of holes through it. A little chisel and hammer and they look like they came from BigAls.


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## cte10 (Nov 10, 2009)

I picked up some lava rock from a cinder pit while in Oregon and used a hammer and cold chisel to shape any "ill-formed" rocks, then a 3/4" masonry bit to drill holes. I've worked with some woods that were harder to shape than the lava rock. Just be sure to rinse well, I found that shaking it under water helps dislodge some of the sediment.


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