Adding dry live rock to an established tank

[JR55]

I have an established 54 gallon display tank with 50 pounds rock and an 11 gallon sump. I need to add a fist sized piece of dry live rock to the system that is about a half pound. Can it be placed in the sump to cycle and then placed in the display tank? If so, how long does it need to stay in the sump?

 

[Dsnakes]

If you plan to add it to the sump first, it may as well be in the dt. All the water is shared with the organics. Most will cycle it in a separate tub with heater/powerhead and do water changes. Probably cause a mini cycle depending on how much organic matter is dead on it

 

[samnaz]

Is it dry as in, dead live rock (pukani, Fiji, etc)?

Or dry as in, manmade/mined rock from inland ancient reefs (Brs, marco, reef cleaners, etc)?

 

[Roy 9121]

I don't see how just adding it to your display tank would cause a problem.

 

[JOKER]

If it is pukani or some other dry live rock I would clean it first!! If not it will leach phosphate for a while.

 

[foxt]

It sounds like you are asking whether or not the rock needs to be colonized by bacteria before you can add it to the DT? It isn't a matter of trying to get bacteria established on it (the rest of your rock will take care of that soon enough); it is more a matter of making sure that you aren't adding anything to the tank besides, well, just rock.

Is it dry as in, dead live rock (pukani, Fiji, etc)?

Or dry as in, manmade/mined rock from inland ancient reefs (Brs, marco, reef cleaners, etc)?

This is the key question - when you say "dry live rock", do you mean that it was rock encrusted with life that has now dried out? If so, it may still be loaded with organic matter, which, if place in your tank, will add to the bioload as well as possibly add phosphates.

Regardless of it's past history, if it is clean, then you should be able to just add it. It's relatively small, so even if it has phosphates bonded to the top layer of rock, it won't do much to hurt the tank right away.

If it has visible dried dead stuff on it, you should try to get that off first. A bath in diluted muriatic acid will burn it off, or you can soak it in vinegar for a few days which should loosen things up and then hit it with a power washer or even just a strong stream from a hose.

 

[JR55]

Thanks for all the input. It is BRS FIJI dry live rock. It looks clean and white and does not appear to have any dead material on it.

 

[JOKER]

I think the dry Fiji rock has as many phosphate as the pukani does so I would cure it as long as possible before adding to reduce algae.

 

[saltyfilmfolks]

I have an established 54 gallon display tank with 50 pounds rock and an 11 gallon sump. I need to add a fist sized piece of dry live rock to the system that is about a half pound. Can it be placed in the sump to cycle and then placed in the display tank? If so, how long does it need to stay in the sump?

Yea it fine. In that water vol. yea.

Fwiw the mini cycle would be from high organics rotting and creating ammonia. If its large vol of water it's minor and you could add a bottled bacteria.

If it's a very soft rock you could get some diatoms , but that's not a mini cycle , and if it's a fairly established tank, you'll prob just see sponge growth rather than diatoms.

Additionaly, I've done it more times than I can count.

 

[marktea]

Added an additional 8lbs dry rock to an existing 10 pounds of live rock in a 13.5 a month in to the tank. Cause a mini cycle that cleared in two-three days

 

[chewy tabacca]

If it is pukani or some other dry live rock I would clean it first!! If not it will leach phosphate for a while.

+1 I just put a dry rock in to cap something off in my tank, 1 week cyano, I am dealing with it now, I test my tank every three days and all parameters are perfect and still have cyano. Nitrate 4ppm and Phosphate 0.12. Definitely be aware of this as I am living it first hand