Do I have to cure old live rock or just use it right away?

[MaverickReef]

I recently bought 75-100lbs of "dry rock" from someone local and it's completely dry and white. It was used in a reef tank many months ago. I'm setting up a 120g when I move in May of this year, and I am trying to figure out if I should start to "cure" this dry rock or if I should just start my cycle with it when I set up the new tank in May.

Do I need to cure this dry rock or just cycle it like normal? I am trying to take this tank setup slowly and do everything I can to avoid algae outbreaks in the future

 

[JAC-]

You can do either, curing the rock should help you get a stronger cycle quicker when you start the tank and if you play your cards right you may get some coraline algae started ahead of the schedule. If you can cure it, why not?

Note of caution; I've heard horror stories about people reusing rock from others tanks, with mistakes the previous owner made coming out of the rock to then haunt you.

I've never reused rock (all my setups are still running and all were with new rock) so I can't say one way or the other on my experience doing it, but thought I'd share the ghost stories with you. Maybe someone that has done that can comment on their experience.

Plan it all out, take it slow, and test your results that'll be the best way to reduce problems in my opinion and it sounds like you're on the right path.

Best of luck to you friend.

 

[Greg P]

Personally, I'd cycle the rock in a tub or 2. Heaters and powerheads. And keeping the Sg close to normal is a good idea. No point waterchanging your whole system to cure rock.

You're going to want to first cure it. When you get it wet, there will most likely be some 'stuff' that will cause a cycle which will pollute the water, so a 'soak' for a week or so then a rinse in new SW is a good idea to see what's coming out of it. During this time you can test NH3 after a few days. Now you'll know if you need to cycle it because of dead stuff.

After you're certain there's no nasties left, you're going to want to let it sit in the tub(s) for a week or so to see if there's an issue with PO4. If not, move on to adding an Ammonia source to prepare it for your DT, and cycle it for up to 3-4 weeks. Then you can do a final rinse and drop it in your DT.

If you don't use tubs, you're going to need to WC your whole system if you need to remove PO4, or High amounts of NO3.

Have fun!!

 

[Greg P]

I meant to add;

You can cycle/cure 30-40lbs of rock in 8-12g tubs. So 100% WCs are cheap.
Not so much when you do it in your tank.

 

[Tcook]

After you're certain there's no nasties left, you're going to want to let it sit in the tub(s) for a week or so to see if there's an issue with PO4.

I agree. If this rock was from a tank that crashed and was left to "stew", it could be a major PO4 sink.

 

[Auquanut]

I'd have to say that if the rock was previously used, and is now white, that it was cleaned in some manner. It's hard to tell how the rock was cleaned, and what's left on it unless the seller told you up front. I'd soak the rock in RO and Prime for awhile. Then cure it and monitor parameters.
Just a thought.