Dry (live)Rock

[Famer]

I have dry live rock that i ordered from bulk reef supply.
From what ive been reading i need to get a few pounds of True live rock to get this dry rock going? or am i wrong about this?

[asylumdown]

depends on what you mean by 'going'

If you add any substrate with a large surface area (i.e., any kind of rough textured, porous rock) and put it in water with a source of ammonia, bacteria that can process both ammonia and nitrite in to nitrate will eventually colonize the surface of that rock regardless of what you do. So in that case, no you do not need 'live' rock to seed your dry rock. From a functional filter point of view, all you need to make rock 'live' is - salt water, a source of ammonia (concentrations of 2ppm are optimal, 5ppm or higher actually becomes toxic to the species you want), and time.

However, to some people the term 'live rock' also means the host of commensal species that live on rocks, such as pods, coraline algae, worms, macro algae, etc. Those critters will not appear out of the ether, so if that's what you mean by 'going', then yes, a source of those will be required, and cured live rock from an established system is a good way to introduce them. It's also a good way to introduce things you'd never want in your tank, so make sure you are getting your live rock from a trusted source.

FWIW, I simply do not believe any live-rock holding tank in any LFS anywhere in North America is free of Aiptasia. Which is why when it was time to add a small amount of live rock to my tank to add all the beneficial organisms that you can't otherwise purchase separately, I cut a deal with the LFS who built my tank to put aside an entire 55 pound box of fresh, uncured live rock from walt smith aside for me on their next order. I met him at his store as he got back from the airport so that my 'live' rock never touched a holding tank anywhere between the ocean and my house. I cured it myself, and my rock was pest free. If that's an option for you, I would recommend exploring it.

The only other thing I'd suggest is to do some in depth googling about the difference between the true nitrifiers, and heterotrophic bacteria in aquariums. Some people cycle their dry rock by adding a raw cocktail shrimp and allowing it to rot in the tank to provide a source of ammonia. This definitely works, but it also adds a significant amount of organic carbon to the water column. 'True' nitrifiers like the nitrosomonas and nitrobacters reproduce very, very slowly from a bacterial point of view, like one division every 24-36 hours or something crazy like that (hence why cycles take so bloody long). They also get their carbon from atmospheric CO2 I'm pretty sure. Heterotrophic bacteria like the ones that break down rotting flesh can divide once every few hours, and they get their carbon mostly from organic molecules in the water. There is a school of thought out there that believes cycling your tank using any rotting organic matter encourages an over-proliferation of heterotrophs that through their rate of division allow them to take surface real estate away from the slower growing nitrifiers, potentially leading to a less stable tank for the first few months that it's running.

Anyway there's lots of ways to skin that cat. Adding pest free live rock to your dry rock is never a bad idea, and it might speed the process up, but it's also not necessary.

[Famer]

So to get coralline algae i will need live rock? Or will that grow from a light source?

[asylumdown]

to grow coralline algae you need a source of coralline algae lol. Whether it comes from live rock, or hitchhikes in on a frag plug or the base rock of some SPS, or you go over to a friends tank and take scraping of it off their overflows it really doesn't matter.

Coralline algae will not spring forth from the ether, just like a sunflower will never grow where no seeds have been planted. There's plenty of different species of coralline as well, different colours and different preferences for light. If you are going to add live-rock I'd suggest picking pieces with lots of different colours on it as you're more likely to get at least a couple varieties that will do well in your tank. I have really high intensity LEDs on my tank and I find that the darker purple kinds won't grow where the light hits them straight one, but it's ALL over my overflow boxes and anywhere there's a bit of shade.

[Famer]

I was thinking of getting 12lbs of Live rock from (saltwaterfish) or (aquatic connection) do you have any experiance with those sites or what are the good ones? Thanks