Making live rock....

Are you talking about the red porous lava rock? If so you may introduce a lot of unwanted elements into your tank from it, very rich in Iron and other heavy metals.
You would be better off with limestone based LAce Rock, its primarily calcium carbonate based and similar to the stuff dumped into the ocean to grow cultured Live Rock.
The other choice is to make it with Aragonite and portland cement. You can shape it to suit you and it provides decent porosity to foster anerobic bacteria for denitrification. Only problem is it takes at least 3 months for typical sized pieces to cure out and leach off all the excess calcium hydroxide(like Kalkwasser) that drives the pH sky high while this stuff cures.
If you do a search on the boards you'll find several sites that go into detail for this process. I use a lot of it as base rock in my reef and its inhabited by all manner of infauna and starting to get covered with coralline algae. One thing you will see is using oyster shell from a feed store> Its cheap, about $3-4 a bag but it leaches phosphate a long time and it looks like crap.
HTH

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I thought I was me, but we were wrong
email: geeflipr@internetcds.com

[kmu]

Whats the easiest way to make live rock out of dead lava rock(the one that you can get out of LFS)What type of lights, filtration, live rock to seed the dead rock? any suggestions would save me alot of mone. THX

[kmu]

I had the lava rock for over a year now in my freshwater tank(with cichlids) and it didnt hurt them, is it safe to use them on a reef?

I wouldn't risk it myself. There are all sorts of minerals in lava rock that dont cause a problem in freshwater that can be a real problem in salt water. It is a more capable solvent the freshwater and different chemical reactions can occur releasing metals into the SW causing toxic reactions in delicate reef organisms. IMO it isn't worth losing your whole reef to save a little money

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I thought I was me, but we were wrong
email: geeflipr@internetcds.com

[Fudge]

Primarily phosphourous and sulphur(ide)i believe ,probably ok in F\W tank,with an acidic base.
IMO,not even worth the risk when you consider the $`s invested when the products done.
Marc.

[kofrederick]

i put lava in my 55g reef and my mushrooms moved on to it and they are huge

[Twitterbait]

they may do fine for a time, but you will likely get some wicked algae growth and leeching of other mninerals and heavy metals into your system. it is not recommended.

[FishFanatic]

Ya i also heard they cause algae.

[tlgreve]

what about red lava rock that has been in a FW aquarium for a long time (like 2 years) Does it still leach?