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Copper question


Feb 11, 2004
I have an acrylic tank I picked up used. Is there a way to tell if copper has been used in it before? Is the concern the same with acrylic tanks? I have always heard that the copper stays in the seams, that's why I ask.
I don't think there is any way to tell. Can you ask the previous owner???

Copper does stay in the seals and there is no way to get rid of it. If there is any chance at all that copper has EVER been used in this tank don't use it for invertebrates especially not cephs!! Get a new tank or a copper free certified one!!!!

you could fill it with fresh water, leave it sitting for a couple of weeks and then use a copper test?
I'd didn't know the original owner.

That's a good idea Colin, I think I'll try that. The reason I mentioned the seal, is that acrylic tanks are fused together, so I don't think it would remain in the seal.
right, i missed you saying it was acrylic... but its worth checking for copper either way... just in case :smile:
Try the Colins freshwater idea......I'd missed the acrylic bit too :bonk:. But be really careful. We have some acrylic display tanks and while we never use copper we had put some iron chain in one (for a human impact display) and the acrylic absorbed some of the iron (don't ask me how!) The acrylic is still stained nearly 2 years later!!!! I s'pose copper may stain acrylic bluish/greenish....but is it worth the risk?


How wierd... I've never heard of acrylic staining like that. Thanks for the input.

I just really like the idea of acrylic for an octo tank, I 've got an idea to make it escape-proof. I plan to drill through the top of the back side for two 1inch bulkheads to act as my overflow (I have the ones with the cover over them) and one 3/4inch bulkhead for my return from the sump. Then, I will have an acrylic, hinged top that I will attach to the top of the tank with nylon thumb screws.

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