Curing Dead Rock

[Dana Riddle]

I bought a used aquarium along with all the goodies (skimmer, RO, etc.) The tank had housed some dead rock and when the previous owner tore it down he placed the dead rock on a outdoors concrete pad where it got rained on for a year. The rock is quarried coral rock and has no sign of calcareous growths, green algae, etc. - it is snow white. I assumed this rock would be clean but since I was going to use some of it to support Florida live rock, I decided to soak it in water. After a few days, on a whim, I checked the ammonia level - and it surpassed the limit of my device (>0.5 ppm ammonia, using a Hach DR890 colorimeter and the salicylate method.) I'm now in the 2nd week of soaking this rock and ammonia is still high. So - don't assume the dead rock is clean - cure it like you would live rock!

 

[VSVP bet]

What happens is when live rock goes to 'dead rock' the organisms and organic matter deep inside the rocks also die, and when the rock gets wet again, the bacteria consumes the dead matter and will release ammonia. Keep soaking the rock in salt water, maybe add a bio start like sea chem cycle to keep bacteria populations high, and do water changes on the holding tank. Its just a matter of establishing the rocks and processing all the dead material.

 

[sbash]

Does this mean the curing process is simplified? Kind of a "Just add water" approach.

For example, when I cure 'dry rock', I add in a seed rock and throw in a dead shrimp (for a couple days). I have never tried to just cycle basic marco style rock off the shelf without seeding it. Interesting.

 

[KrisReef]

Nice. I did the same trick with dead live rock except I tested Phosporus and had to dilute the water to 4:1 to not peg the Hanna Ulr phosphorus Checker. I still had nearly the upper limit of 200ppb. ( I don’t recall the number measured)

Curious if you measured you white rock for other nutrient parameters?

 

[Dana Riddle]

Does this mean the curing process is simplified? Kind of a "Just add water" approach.

For example, when I cure 'dry rock', I add in a seed rock and throw in a dead shrimp (for a couple days). I have never tried to just cycle basic marco style rock off the shelf without seeding it. Interesting.

I seeded the container with a chunk of live rock from an established tank once I realized the ammonia spike, and have added Fauna Marin Reef Bacto Balls. Also added a heater to speed the biological processes up. Since this rock had been in an established tank and then wetted by rain for over a year I had incorrectly assumed that the rock was rinsed of nitrogenous matter.

 

[dantimdad]

I actually hoped that would happen with my dead rock. Yes, I am crazy.

I was trying to see if the addition of microbacter7 and bacto balls would be effective at cycling previously dead rock and how quickly it would drop the ammonia levels. I have left it alone for a week without measuring again.

Will measure this weekend.

 

[cracker]

I like to soak all new dry rock in a darkened barrel. This leeches out all the Po4 ,No3 Am & everything . When the levels are low enough I then I cure it as usual. Folks , This takes a long time & requires a "lot"patience . I had to cook (soaked in dark barrel) for 11 &1/2 months .

 

[Peter Clark]

I like to soak all new dry rock in a darkened barrel. This leeches out all the Po4 ,No3 Am & everything . When the levels are low enough I then I cure it as usual. Folks , This takes a long time & requires a "lot"patience . I had to cook (soaked in dark barrel) for 11 &1/2 months .

When you cooked the dry rock, did you do so in saltwater, brackish, fresh rodi, or tap? I assume saltwater, but since it is before the main curing I wonder if it really matters. I have a bunch I need to do this on. I'm a long way from setting up the tank so don't care as much about curing right now.

 

[cracker]

Hey Peter , I meant newly made salt water. In my experience using dry rock whether from a older tank or just bought. It all has excess Po4& no3 in it. the new water draws out these nutrients in the rock. they are sprouting algae like crazy.
I have a small batch of rock now that's almost ready to get swapped out whith a couple of problem rocks I have in my tank now. In fact I'm about to test it now.

 

[danschoenherr]

I also acquired a bunch of "dead" rock from someone elses tank that had been dry for a year or two. I first soaked it in water for 3 weeks, then gave it a muriatic acid bath, rinsed and dried. Then a bleach water bath followed by a rinse and 2 weeks to dry in the sun. After all this I had the rock in a barrel of circulated saltwater with Prime added for 4 months, then seeded with Dr. Tims and a chunck of live rock from my tank. After all that, I ended up with a major hair algae problem that I am still dealing with. Those rocks can hold a lot of crud in them.

 

[twerdine92]

I'd always check the water levels when curing "old dead rock" for copper. You never know what people did to their system and tanks before you had them. Just my .02