Even rocks deserve another chance! Would you reuse old reef rock in your saltwater tank?

[Peace River]

Even rocks deserve another chance! Would you reuse old reef rock in your saltwater tank?

Recently I have seen a few threads asking about reef rock that has been sitting somewhere dry for a few years or more. The questions revolve around if the rock is still useable and, if it is useable, determining the best way to prep the rock to be ready for a reef. What do you think – can old reef rock be reused in a reef tank and is it worth the bother? If you believe that it can be reused, then please tell us what you would do to prep the rock. Are there different steps to rejuvenate the rock if it has been sitting in a tub of freshwater vs. being dry when stored? Also, please let us know if there are situations where you wouldn’t reuse the rock.

Photo by @Clutch


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[CasperOe]

I keep my old reef rock in a large heated Brute trashcan to always have some on hand should I get a good idea and set up yet another tank Wouldn't think twice about using it again, I am off the firm belief that the benefits outweigh the pests.

 

[cdnco2004]

Soak old rock in a 10:1 bleach water mixture for a few days then let dry out completely and your good to go.

 

[albano]

I have old ‘live’ rock that is probably older than many members here! Started reefing in the 80s and helped a friend with a LFS order reefing items. Personally went to LA wholesalers and Florida Keys suppliers to order and check out their operations.
Some of that rock has been left outside, kept in trash cans with and/or without water, and is still sitting waiting for another chance at life!

 

[PeterErc]

Old rock all the way, bleach, acid wash.
Been done more than once.
Bought some dry rock, seller said he bleached cause he had algae growing all over it. Algae came back, 7 day bleach bath acid wash then peroxide spray for good measure.
Then previous startup all dry recycled rock

 

[Gumbies R Us]

If I ever decided to upgrade my tank to a bigger one (more than likely when I get a bigger place haha) I would reuse the same rock that I have right now.

 

[Idoc]

I've acid washed some old reef rock once. It worked well, but it is not something that I would recommend to a novice reefer.

 

[Dburr1014]

I used reef rock for a couple of years and then gave it to my brother-in-law. He used it for probably 15 or so years and left it outside when he was done with it. I took it back from him and gave it a muriatic acid bath and put it in my current tank which has been set up for almost 10 years.

 

[randomfishdude]

When I was upgrading my tank I had to get some more rock. And my lfs had their rock tank empty because the bulkhead has sprung a leak. I used some of the rock from it and I have had 0 issues.

 

[Jeremy_d]

When I tear down a tank, part of my process in doing so is preparing a tub to keep the rock alive (Powerhead and heater in the winter). Live Rock is too expensive to be throwing out like that

 

[Rusty_L_Shackleford]

Absolutely. I started with rock a guy gave me that had been sitting in his yard for awhile. My process;

1) Pressure was it. If not an option just blast it with the hose
2) soak it in blwach solution for a week I used RO because I have a unit so why not.
3) rinse the rock and then soak in dechlorinatorand RO
4) 2 x multi-day soaks in RO.

Might be overkill but I was still putting together the tank so I wasn't in a hurry

 

[kevgib67]

I kept all the previous live rock that I had after my tank tear down about 12 years ago. I bleached it in the sun then rinsed it and dried it again in the sun. It was all placed in a trash bag and then put into another trash bag. Although my main structure is all live rock, I used a couple of pieces of the old rock for a zoa and gsp garden. I just rinsed, dried and in it went.

 

[kevgib67]

I kept all the previous live rock that I had after my tank tear down about 12 years ago. I bleached it in the sun then rinsed it and dried it again in the sun. It was all placed in a trash bag and then put into another trash bag. Although my main structure is all live rock, I used a couple of pieces of the old rock for a zoa and gsp garden. I just rinsed, dried and in it went.

 

[o2manyfish]

When we built our 750g, upgrading from 400 a year ago we needed more live rock. I had collected 100's of lbs of rock over the years from other breakdowns. I also had about 400lbs of rock from my last tank crash. When the tank crashed (sump blew a seam and topoff came on and kept trying to refill it) we ended up with the 400lbs from the sump which were covered in dead zoas, xenia, clavularia, gsp, mushrooms. The other 300+ lbs had been sitting in buckets, tubs, milk crates on the side of the guest house for over 10 years accumulating all that mother nature could drop and pour on it.

We took a 150g rubbermaid tub and made a strong concentration of Citric Acid. Then Soaked the rock for 48 hours. We then pulled the rock out (and thankfully) put it on a tarp in the back yard to clean it off with a presure washer.

The Citric acid not only broken down all the dead life on the rock work, but it actually etched away the surface of the live rock - Getting rid of the coraline and algae on the rock. When we pulled the 700lbs of rock out of the tub I was blown away to find almost 30lbs of sand sitting in the bottom of the bin. The Citric Acid literally dissolved the surface off the rock.

When we started presure washing the rock it was like milk with calcium washing off. It took several rinses with the pressure washer. Then a soak in tap water, and another pressure washer.

When we filled up the tank with water for the first time there was still a very fine layer of silt that came off the rock but it cleared up in about 36 hours.

The rock was immaculately clean to start with and quickly grew all the appropriate crap and looked seasoned right away. We used 700lbs of fresh rock and 300+ lbs of active live rock.

The brown, grey on this rock is a biome that developed within 24 hours of the rock going in the tank. 72 Hours after water was in the tank it was gone and never seen again.

This is the sand created by acid washing the dead rock. There was no sand in the rock bins or tubs, this was all created by soaking the rock.

72 hours after filling - The 750g is just the display of a 1500g system. So when we added all the fresh live rock and water we just ran it for 24 hours then opened the valve to connect it to the system and added fish and corals immediately.

6 months later.



Dave B

 

[cdnco2004]

I've acid washed some old reef rock once. It worked well, but it is not something that I would recommend to a novice reefer.

Bleach baths are super easy for anyone who can follow basic instructions. Fill tub with water and enough bleach to equal 1/10th the amount of water in the tub. Add old live rock. Let soak for a few days. Drain then layout the DEAD rock on the floor so it is completely exposed to the air. Let air dry for a few days and then your done. It is an extremely easy process anyone can follow.

 

[GARRIGA]

Only solution I see to getting Fiji, Tonga or Pukani unless those options open up again. Bleach and sun dried would be my approach.

Currently swap between dry rock as I often change the scenery but since from my tank just let sit in the garage dry for an extended time. Could be months or year plus. Just check to see if any mold developed but haven't seen that yet and since I let sun dry outside before storing then not expecting that to be seen.

 

[JaimeAdams]

All of the time. I'm a firm believer that the rock and pores of the rock are the biological filtration of our ecosystems. That being said I am not a big fan of these man made "Real" "Life" or other names tossed on to ceramic, porcelain or cement based structures. I've been selling rock, breaking up rock, creating aquascapes for long enough to see the real difference that actual rock from the ocean is compared to what is commercially available with regularity these days.

 

[cdnco2004]

Only solution I see to getting Fiji, Tonga or Pukani unless those options open up again. Bleach and sun dried would be my approach.

Does not mater where the rock comes from once it gets bleached its no longer any different from any other rock. Nothing that made it "Fiji" etc will remain once it has its bleach bath.

 

[kevgib67]

Does not mater where the rock comes from once it gets bleached its no longer any different from any other rock. Nothing that made it "Fiji" etc will remain once it has its bleach bath.

The dry, dead rock I have from my previous tear down is extremely porous and light. The porous nature makes for much more surface for bacteria to colonize.

 

[cdnco2004]

The dry, dead rock I have from my previous tear down is extremely porous and light. The porous nature makes for much more surface for bacteria to colonize.

Take your expensive Aragonite dead coral live rock from fiji and put it in a beach bath and it will be no different that much much cheaper Aragonite dead coral from the Florida Gulf. What your paying for is the different "life" that comes on those rocks from those various regions when they are still alive. Once it goes in the bleach where it comes from makes zero difference.