Tank Suitability after Copper

[Brian Ward]

A fellow reefer mentioned that the silicone joints in a glass tank may absorb copper and make the tank itself unfit for coral (SPS specifically). I know that rock and sand will absorb the copper and leach it back into the water but I hadn't heard that about the silicone.

 

I have a 120 that I used as a hospital/QT tank briefly and treated with Cupramine (Cu concentration stayed below the 0.6mg/L threshold). This is a tank I had planned to use as an SPS reef but hadn't completd the setup, so with it empty and available it seemed like a good option. Can I still use this tank for SPS after draining and cleaning? Has anyone heard of the silicone joints leaching copper into the water?

 

~Brian

[gastone]

Brian, you may want to check with one of the guys over on the chemistry forum on RC. Dr. RHF is back and awesome as ever. I think a thourough cleaning would do the trick, but then again...

 

Garrett.

[ReeferMan]

Usually copper will turn the silicone blue. Is yours blue?

[Brian Ward]

Usually copper will turn the silicone blue. Is yours blue?

 

Not blue. Still clear. I'll post over on RC to see if I can get any other info.

 

~Brian

[ReeferMan]

i would rinse really well and go for it. If your really worried about it. Fill it and let it sit for a few days and test it for traces of copper

[Brian Ward]

For any interested, Randy gave me this answer:

 

IMO, silicone will not absorb any worrisome amount of copper, but the glass, and especially any deposits on it, will have to be carefully cleaned with acid. Search on this forum for acid and copper and you'll see many descriptions of the process.

[davelin315]

Hmmm... that's an unexpected answer! I figured glass was inert and wouldn't absorb anything. Guess I'm wrong!

[Brian Ward]

Hmmm... that's an unexpected answer! I figured glass was inert and wouldn't absorb anything. Guess I'm wrong!

 

it's not actually the glass that absorbs it, but mineral deposits on the glass. I think this is applicable with used tanks, but since this one was brand new I don't think there were any deposits on the glass to start with. so as best as I can tell using the copper didn't harm the tank.