Muriatic acid for live rock
 

Does anyone know the procedures of using muriatic acid to resurface the live rock. My rock got copper in it thats why. All I know so far is that its a dip treatment 10:1 ratio of water to muriatic acid respectively. How long does the dip last?

You can use it but have heard different views on leeching. I would use bleach or vinegar. The bleach is all I have ever used and there is no problems with it and it will take care of the copper. Use about 1 cup to five gallons is a good rule of thumb. Let it completely dry out in the sun. Takes about a day but it is colder now so allow for more time. The bleach from what I understand breaksdown in approx. 24 hrs. but I always let it dry before putting it in the tank to be safe. Oh 1/2 & 1/2 for the vinegar.

Thanks terminator :), but does anyone know the process of dipping rock in muriate acid, eg how long and what to do after?

I don't see how bleach is going to remove copper. The goal of the acid is to etch the surface of the live rock. Vinegar should work, but it's going to be slow and more expensive.

You just have to rinse the rock well after the treatment. The acid will not stick to the rock, the rock will actually be neutralizing the acid as it is eaten away.

vinegar method
 

How deep does the copper get absorbed into the rock?
How long do you let the rock soak in vinegar to remove the copper. Whats to prevent the copper in the vinegar solution from re-attaching to the newly cleaned rock before you can remove it and rinse it?

Copper is adsorbed onto the surface. It could be buried by coralline growth, but otherwise, I don't know of any mechanism to move it into the rock. The copper is soluble at the pH of the treatment.

I don' t believe that rinsing will remove copper from the rock. I don't the the precipitates are that soluble.

I don't know Bertoni the chemical breakdown I'll leave that to the chemist. But I do know that from my experience with dosing quite a bit of copper into my tank back a long time ago from some bad advice from the kid at the LFS. I took bleach and washed the rock everything in the tank ( thank God it was all fish only). I tore the whole tank down and started over. After bleaching it I returned the rock and equipment put a few crabs snails and such in there to make sure everything was safe. Everything lived and I went into reefing then and gave my Trigggers and other aggresive fish away. Sorry for the long story but the bleach does work.

nice info everyone, but does anyone know how long the dipping process is?????

If you going with the acid I would think only a few hours should do it.

Longest ive heard so far is 1/2 hour but i really dont know :(

If you're going to use the muriatic acid, 20 minutes should be fine. I'd watch the rock and see how much is dissolving. Removing a thin surface layer is enough.

thanks bertoni! finally found the answer ive been searching for all day :)

I'm sorry nmhs I haven't ever used the stuff, but just thinking about the acid eating at the rock it surely can't be left in long. 1 maybe two hours is all I would go. If somebody that has had the same experience as you said 1/2 an hour and it worked for them that's what I would do.

I would do the dip a piece at a time, and try to judge the amount removed. Please be careful with muriatic acid, if you use it.

Thanks term and bertoni, im just so glad theres a solution to getting copper out other than buying more rock

Good luck to ya!

Copper is an odd duck in an aqueous solution when dealing with carbonates. If a carbonate is growing it is adsorbed into the structure. If if it is more or less a nongrowing surface and fresh it does not form a distinct precipitated phase on the surface, but interacts with the CaCO3.

Once thing that may be common is the cooper binding with some organic on the surface of the carbonate. Bleach does not do much for copper bound into the carbonate but as and organic on the surface may be a different issue.

It is quite common in biology, geology and soil science to use house hold bleach to clean the surfaces of carbonate minerals of organics leaving the surface and any pores nice and fresh. This may be what is going on when we rinse/soak corals/rocks of carbonate in bleach. It is kind hard for bleach to dissolve carbonates when house hold bleach has pH of ~12.

There use to be a product similar to Cupramine, called AntiCopper, that would take all copper out of the filter bed or "stuck" to carbonates but is no longer marketed.

Thanks, Boomer! I've never done any of the acid or bleach treatments on live rock or sand. I just don't know much about the subject.

Sure Jon but as you said Copper ionically bound to the carbonate is not going to be removed by bleach much, if any at all, as it is part of the crystal lattice just like Ca++ or Mg++.

Thanks Boomer, I too do not know how it worked for me other than I was not at the time adding anything for it to really mix with like Ca/Mg. It was at the time fish only with base rock. So I guess thats the only way it cleaned my system. I do know after the problem the snails and all lived and I didn't have any problems after. But I do thank you for the good info because the last thing I want to do is give bad advice to anyone even though it worked for my situation. But I do see now how it could bond with calcification and have to be eaten away by the acid.

You bet Tim ;)

I often do acid washes on old LR when I'm rebuilding a system for a client, but generally more as a preventative and to kill Cyano than anything. This rock then becomes base rock.

For me at least, the length of time for the acid wash greatly depends upon the porosity of the rock... If the rock is extremely light and porous then it gets less time, if it's very dense and heavy, it gets a much longer soak time.

-Tim

Exactly tgreene thats what I found out

Where do you get this acid? It's Hydrochloric Acid right? What product and where?

Thanks