Advice regarding copper

[awestruck]

I was trying to help someone new to the hobby and discussed the danger of copper leaching into the water, as it had once been a freshwater tank. I clearly stated that if copper was EVER used in the tank, it could be a catastrophe waiting to happen. Please correct me if I'm wrong about this because I do not want to be giving beginners incorrect information.

[disc1]

You are correct sir.

[bertoni]

Live rock definitely is an issue. A tank might be able to adsorb enough copper to be a problem, but no one has ever run the experiments, as far as I know. A good wipe-down with vinegar will remove copper, provided all the calcium carbonate deposits are removed, too, so it's not a critical issue.

[disc1]

I'm not sure that vinegar will remove copper. It might on the glass, but copper will get into the silicone and that's where the problem is. It leeches back out into the water and can kill. It might not, but why take a very expensive chance?

[awestruck]

Yes, I'm aware that if it's in the rock it will be an issue. This supports what I've been taught that if is there, a possible catastrophe is waiting to happen.

[awestruck]

I'm not sure that vinegar will remove copper. It might on the glass, but copper will get into the silicone and that's where the problem is. It leeches back out into the water and can kill. It might not, but why take a very expensive chance?

It seems a consensus is difficult to reach. I've spoken with many people who have lost animals due to copper. I feel it's a dangerous attempt if the tank was treated in the past.

[Randy Holmes-Farley]

Are we talking about just a glass tank? IMO, that can be adequately cleaned. :)

Live rock is more challenging, and live sand I'd just toss.

[geaux xman]

i've read some mentioning that with big tanks, a good vinegar wipe down is adequate for previously used copper tanks. and whatever that is adsorbed in the silicone, even if it leaches out, it is very minimal and is diluted out in the big tank.

comments?

[HighlandReefer]

The amount of copper that binds with the silicon from this research article seems very small and not enough to worry about in a reef aquarium. In this experiment they even sliced the wafers up and run tests on the interior areas of the wafers. ;)

X-ray Absorption spectroscopy on copper trace impurities on silicon wafers
http://www-project.slac.stanford.edu/ssrltxrf/Publications/MRS_2002.pdf

[HighlandReefer]

Copper will attach to calcium carbonate deposits on glass and silicon. Hence the use of vinegar or muriatic acid to remove these deposts.

Re-using a glass tank once treated with copper will not be a problem as long as you properly clean it up and rinse well. I have re-used a freshwater tank treated using copper myself without problems. ;)

[Randy Holmes-Farley]

I don't generally believe that copper in silicone is an issue. I think many times, if not all, the blue color people observe in silicone is not copper, but a blue organic drug (like methylene blue). Copper is just not the type of molecule that will soak into the very hydrophobic environment of a silicone sealant.

If any copper does penetrate, and it does not come out with washing, then it is not going to rapidly come out in any other setting, like an operating aquarium.

The big places to worry about copper, IMO, are inorganic and organic deposits on the glass.

[awestruck]

Thank you for your prompt and well informed answers. :)

[Randy Holmes-Farley]

:thumbsup:

If your friend proceeds, let us know how it works out. :)