Copper Gone...Maybe?

Hugh Mann · Jul 10, 2020

According to my math for the water changes I have done and Cuprisorb, the copper should be completely gone from my tank by now. However my Hanna checker is still reading 0.04 over a couple different tests.

Could it be leeching from something? No rock or sand, just pvc pipes. Could it maybe be from the filter media?

According to the Hanna's instructions, it has an accuracy of +/- 0.05. Seems like a pretty large error bar for something that requires a pretty specific dosage. Anyways, if I am understanding that correctly, it is possible I have zero copper, but the hanna is still registering?

I'm inclined to believe it's gone because ever since my last water change, copepods have covered every square inch of glass.

What do you think? Suggestions?

ichthyogeek · Jul 10, 2020

What’s the filter media? Is the tank glass w silicon seal (I’ve heard those leach sometimes)? I...recommend biological uptake ie macroalgaes

. Are you holding off on corals or something in order to get copper levels down?

Hugh Mann · Jul 10, 2020

A combination of filter floss and aquaclear sponges.

Glass with silicone. I have heard that, but I have also heard it is false?

I thought copper would kill macro algae? Not that I have any on hand.

This is actually my display tank. Or more accurately my former display. I removed all my rock, sand, corals and inverts to treat for Velvet, as I did not have a QT at the time, hence y'know, the velvet.

I really want to put my rock and everything back in to actually have a proper display again, but I know if there is any copper, the rock will absorb it to randomly leech out and kill corals/inverts.

ichthyogeek · Jul 10, 2020

Hmm, I’ve heard that if you fill the tank with something acidic like vinegar, it helps leach more copper out. You could also do cross tests with RO/DI water or freshly mixed salt to determine if it’s really false positives as well!

Regsrding copper killing macros: anything will kill something else in the right amount. If it’s as small as .05 ppm, I’d be willing to bet a small amount of disposable chaeto that macroalgaes could uptake it for later disposal.

jsvand5 · Jul 10, 2020

I’d just run your tank like normal but keep a bag of cuprisorb in there as insurance. That what I did and never had any issues.

Hugh Mann · Jul 10, 2020

I have Cuprisorb in there right now. Unfortunately all I had in hand was chelated copper, not ionic, so it's super slow. Have poly filter on the way too.

Might give that a shot. And just give it a few more days and tests before inverts. I didn't plan on the removal process taking so long.

JumboShrimp · Jul 11, 2020

I was told that the Hanna Hi-range Copper Checker (excellent for monitoring copper treatments) is not as accurate at very low ranges; could your 0.04 really be zero? Just a thought. Best wishes.

Hugh Mann · Jul 11, 2020

That's kind of what I am thinking, might be zero, but I have no other test.

It's the copepods that make me think so. They vanished the day after I started dosing copper, and now they're back in the thousands. I'm certain like all other inverts they are killed by copper.

I just don't want to chuck a bunch of copper sensitive critters in there and have them all die. :/. Is dilemma.

Randy Holmes-Farley · Jul 11, 2020

Hugh Mann said:
According to my math for the water changes I have done and Cuprisorb, the copper should be completely gone from my tank by now. However my Hanna checker is still reading 0.04 over a couple different tests.

Could it be leeching from something? No rock or sand, just pvc pipes. Could it maybe be from the filter media?

According to the Hanna's instructions, it has an accuracy of +/- 0.05. Seems like a pretty large error bar for something that requires a pretty specific dosage. Anyways, if I am understanding that correctly, it is possible I have zero copper, but the hanna is still registering?

I'm inclined to believe it's gone because ever since my last water change, copepods have covered every square inch of glass.

What do you think? Suggestions?

I would not rely on this device at these levels. This device is not suitable for monitoring copper in a reef tank at these low levels. At the low end it is not accurate, as has been shown by people who have gotten results like you, then done ICP and seen little to no copper.

Many folks see detectable opper with it, and few see anywhere near that much by ICP.

I would get an ICP test if you are concerned about copper.