live rock question

Reinvent

New member
Hello everyone. I just purchased about 150 lbs of LR from a craigslist ad. Great deal on the rock and I am finally on my way to getting my tank going. The guy had the rock in a saltwater tank, then decided to get out of sw and put it in his freshwater cichlid tank. About half of it is covered in green algae.

My question is should I cure it like I would regular "dead" LR? Is there any reason to be concerned that it could now have something in it that would harm the growth of my up and coming sw tank? I am new, but have tried to do my homework on starting my first tank right.

Thanks for any advice!
 
There shouldn't be anything particularly harmful but it will need to cycle all over again so I would consider power washing them, then a good rinse in RO water to finally go back in the saltwater
 
I was considering scrubbing it with a brush to get as much off as I can first. Love the powerwash idea as it would get into the crevices much better. Hopefully that should reduce the cure time somewhat by getting more organic material off. Great idea.
 
Over time the rock will have saturated with nitrate/phosphates freshwater can go way higher than salt so you will have a long curing process before the nitrates are reduced. Look into an acid bath and remove everything organic you possible can. But be warned you will likely have a few months before your nitrates are reduced. Add a refugium soon and only add a few fish until your nitrates are down to ~10.
 
The algae is a problem. Not sure how to do the acid bath. I plan on getting as much off as possible and curing it for a month or two. I'm nervous about putting it into a tank until I am absolutely sure it is stable. I still don't have a tank yet so I've got time. I just couldn't pass up .50 cents/pound. It's enough rock to do all I want and then some. Planning on putting it in a 75 gal with a 40b refugium. Lots to get before any fish show up here! I've got lots of freshwater experience but this is my first sw. I just need to be patient and do it right.
 
Any chance that guy treated his freshwater fish with copper? That can be bad for saltwater fish, but not sure that it would be trapped in the rock.
 
Wow, hadn't even considered that. I've still got his number. I'll call him and find out. He seemed to be helpful and just wanted someone to use the rock instead of it being wasted. If he did my "good deal" wasn't so good.
 
Previous owner said no copper so I'm good there. I looked into the acid bath and I'm not really comfortable messing with that unless absolutely necessary. So far I've scrubbed off all the algae I could reach with a toothbrush and clean water. (About half of the rocks, I'll finish the rest tomorrow). It seems to be coming off fairly well, but there is a greenish hue left in some places.

Question: Should I bleach the rock to kill off all the rest of the organics I couldn't reach? It would kill this stuff off and give me a more sterile start to the curing process.

Thanks in advance for opinions and advice.
 
Sorry hit post to early...

Don't use any bleach. It is to hard to rinse and will kill everything including your
fish
 
Don't do acid bath or anything like that - if you do that then you are killing live rock purposely which doesn't make sense. There are two reasonable/ntelligent options if it's been in water the entire time as your post suggests: (1) it can be tranferred directly into a tank, or (2) if you're concerned about algae on it, you can cure it for a week in darkness with a few water change. IMO don't do anything other than one of these two options.
 
Don't do acid bath or anything like that - if you do that then you are killing live rock purposely which doesn't make sense. There are two reasonable/ntelligent options if it's been in water the entire time as your post suggests: (1) it can be tranferred directly into a tank, or (2) if you're concerned about algae on it, you can cure it for a week in darkness with a few water change. IMO don't do anything other than one of these two options.

It was in a freshwater tank--in other words it will introduce dead bacteria and algae in a saltwater tank--scrubbing is that right way to go.

others here do muriatic acid, vinegar, and/or bleach baths. not sure about that.
 
It was in a freshwater tank--in other words it will introduce dead bacteria and algae in a saltwater tank--scrubbing is that right way to go.

Bacteria generally doesn't die, unless exposed to extremes like anti-biotics, UV sterilization, high temperatures (boiling), etc. At most it goes dormant, as it is highly resistant to starvation.

Algae is most effectively neutralized by dark curing. Scrubbing only removes what you can see and access.

I only respond to folks' questions on RC if I know what I'm talking about.
 
so you're saying that fresh-water bacteria and algae wouldn't die off if transferred directly into a salt-water tank?
 
There shouldn't be anything particularly harmful but it will need to cycle all over again so I would consider power washing them, then a good rinse in RO water to finally go back in the saltwater

It would be able to be used straight away with out anything done to it and start it cycling, but of you want to do some work then this is good advice, any more than this and you are wasting time and energy.
 
LOL, I'm not saying it, but rather re-iterating what biologists say about bacteria. I don't have that expertise and instead learn from researching. Salt, whether present in seawater, or present in a much lesser degree in freshwater, is not a factor to the bacteria.

The algae will die off if you run it dark without nutrients in the water, which is done by curing/water changes. This is compared to cycling with the rock, a process where nutrients will be made available to the algae.
 
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Interesting discussion on the bacteria. I haven't researched whether or not the bacteria present in a fw tank is similar or the same as a sw tank. I know that it must be present in both to "eat" the bad/undesired chemicals and change them to good/non toxic chemicals. (Forgive my broad generalization on that as I think we all get the point). My caution on this subject is that I haven't seen anything relating to freshwater bacteria/algae exposure to a closed sw environment. Also my limited knowledge of what really happened during the LR curing process puts me at a great disadvantage. If I wanted to be completely sure that all life on the rock is eradicated I could do the acid bath. I don't want to do that as it is potentially dangerous and also dissolves the rock somewhat giving it a less desirable look. Imo. As for the bleaching or vinegar options I am more open to that if necessary. I just don't want to introduce anything to it that could possibly kill fish/corals needlessly not to mention the loss of $.

I'm going to Scrub as much green off as I can and get it in a tub of saltwater for now. No lights, just a heater, pump and some water changes.

Thank u for the responses and I hope for more advice and discussion. This site is an amazing tool.
 
Well truth be told it won't hurt your tank to kill the rock with chemicals if that's the way you choose to go. There are many many methods to this madness. I just give my opinions, and that's all they are.
 
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