Of course, you don't get any good, interesting life either.

That's how it is with live rock. People have very different expectations of what is considered live rock. For some, LR is just a place to grow bacteria. For me, LR should be full of all kinds of life and have gone as quickly as possible from the ocean to a tank where my best efforts will be to keep as much alive as possible. (including unfortunately, some things I would prefer not to have)

just make sure you see it in their system, if not i wouldnt trust it as much

Hmm. Well, time for my 0.02...

What is sold as 'live rock' and what is sold as 'base rock' are DIFFERENT but SIMILAR. Don't let anyone tell you otherwise, it has more to do with the density and shape of the rock. Heavy, boulder-like chunks are sold as 'base rock' and are exactly the same (ostensibly) as 'live rock' in that they contain life (much of which you won't see in the store). My 'live rock' had little more than some coralline on it when I bought it (though some was obviously a dead coral head), but also contained, unseen, a plethora of fanworms, a small crab, various other worms, the spores of various macro-alga, both stomatella and colonista snails, and at least 3 more colors of coralline algae. Pretty 'live' once it gets into a tank without being nuked (though it looked pretty dead to begin with). The difference is that a chunk of this rock weighs 4 lbs. A comparably sized chunk of 'base rock' would have weighed twice that and had half the amount of caves, crevices, etc. ie: had less surface area for colonization. 'Base rock', if it comes from the ocean, should also have a lot of life involved.

If you're looking for plain white rock (which will eventually turn green and brown and probably purple) and are not interested in all the cool sea life, by all means buy dry rock. You won't get any hitchhikers (good or bad), but remember also that this will severely limit the variety of life in your tank, and you'll still have to deal with things like GHA. I'd rather have a growth of coralline (and other life) already started when I put the rock in the tank, personally.

If you're worried about pests, just be aware that a tank started with dead or nuked rock is just as at risk for introduced pests as one started with live rock.

And again, base rock and live rock both contain life, it's more about the shape and density of the rock. Base rock is just that, rock that is used for the base of your live rock structure. I don't have any in my tank, but looked at some in a store and it just looked like big boulders... with fanworms and coralline algae :wink: DEAD or DRY base rock will obviously not have any life on it. As far as telling if it's 'live rock', I would look for some sort of encrusting growth (like coralline algae) on it's surface.

+1... i got into this hobby to see some weird, wacky outrageous stuff living in my tank, and with nuked rock, you'll never get that. you will get a very boring monoculture of life with just enough stuff to qualify as biofiltration. straight from the ocean into my tank.. ill deal with whatever pests i might get. there's fish or chemicals for just about everything.

Thanks for everyone input!!