Sterilizing live rock

[reiverix]

I just realized today that I had about 7 pounds of live rock sitting in the garage in a bucket. I put it there last weekend when I was upgrading my tank and then totally forgot about it. This was some base rock with no real life on it except coraline but realize it will be unsafe to put it back in my tank after sitting in the cold garage for a few days.

Is there any way to get it prepared to make it tank safe?

 

[OrionGirl]

Treat it like uncured rock--scrub off any obvious dead organics, rinse well, sit in a tub of SW, test on day 3 for ammonia.

 

[reiverix]

I ended up putting it in a 2.5g tank with powerhead and a 1:5 ratio of bleach:water. I let it run for 2 days then rinsed it out followed by another day in distilled water. Rinsed again and added a large dose of Prime. Ran it for another day and now it's been sitting out to dry.

The rock looks pretty white and clean now. Should it be safe or should I let it sit in saltwater and check for ammonia, though I doubt anything has survived the bleach and exposure to air.

 

[Crown Royal]

Being quite porous, live rock tends to absorb many things including bleach. I'd have some concern regarding chlorine slowly leeching back out regardless of whether you added de-chlorinator or not (although you did only have it soaking in the solution for a few days).

This is why you never treat a tank containing live rock with copper medication as the rock absorbs the copper rendering it deadly to all invertebrates in the future.

Live rock by itself is amazingly resilient and simply re-curing it by letting it sit in heated and circulated SW as OG suggested would have "brought it back" in a period of a few weeks at the most. Don't be worried about die-off on the rock - it's actually not a bad thing as it feeds the bacteria that you need for nitrification.