Copper and Inverts

[Sour137]

Hello all,
So I am currently taking online classes and one of those classes is a chemistry class. In the experiment I did yesterday I used a small amount of copper sulfate. The experiment requested that all test tubes and such be rinsed with purified or distilled bottle water. Since I do not drink bottled water, I used my RODI water. The way I would rinse the test tubes was to pull water from a container which held the RODI water with a baster, fill the test tube, and then pour the rinse water into another container. In this process some of the rinse water may have been exchanged from the rinse cup, to the RODI water filled cup. Half way through the experiment I had to refill my RODI cup, and I fear that a small amount of the copper sulfate in the RODI cup may have entered my RODI basin, and possibly contaminated it. I have several inverts in my tank, so naturally I'm quite concerned about using that water for a water change I was going to do today. I did a little math, and for the 20 gallons of water in my basin there would have to be around 2.27 mg of copper in the water for it to be potentially lethal to my inverts. While I did not directly drop copper sulfate into the basin, I am concerned that a small amount could have transferred while I was refilling the RODI cup. I know there is a lot of unknowns here, but do you think that during the refilling I transferred 2mg or more copper into my RODI basin? If I did obviously I would need to dump all 20 gallons of it, or use it in a hospital/quarantine tank that I have not set up yet, but would I also need to get rid of the basin because it too is now contaminated?

A little research says that anhydrous copper sulfate is about 25% copper, and 60% water, and I used about 0.4mL of the copper sulfate in the experiments. The rinse water contained about 250mL of water most of which was emptied from the RODI rinse and into the additional container. If the copper sulfate weighs similar to water then 1mL=1g then the maximum amount of copper that could have been transferred into the RODI basin for it to be lethal to my inverts would be 6.8mL. I'm still fairly new to chemistry so my numbers could be wrong by a little or a lot. I'm fairly confident that there was less than 10mL left in the RODI cup, and I'm also fairly confident that all of the water in the RODI cup did not transfer to the RODI basin.

What do y'all think?

 

[TheRealChrisBrown]

My thought was to always play it on the safe side and ditch the water. But then you exactly hit on my second thought which was contamination of the basin. I've never used copper before, but obviously there is a lasting effect with it because when people sell QT tanks they seem to always mention if they used copper in it. I hate to say it, but if you are worried then I'd just replace the basin as well. Err on the side of caution. If you haven't set up a QT tank yet, save the basin and use it for that maybe?

 

[aquarius]

While copper can be lethal it can also be pulled from water, rocks etcetera very easily. The lack of exact known volumes would be my only concern here. Something you didn't mention and may or may not be aware of is that copper will be absorbed into your rocks and sand until it reaches its saturation point and remains free within the water column where it is able to harm your livestock. Many misconceptions about copper exist spreading fear through the reefing community. Copper does not absorb into glass or acrylic tanks, silicone, food grade containers or most plastics such as the commonly used ace rotomold reservoirs commonly used to store water. For these items a good wash/rinse should be fine, if you're really worried wash with a mild hcl solution and give it a good rinse. Copper will absorb, very readily I might add into live rock and sand and can play havoc on a reefer trying to maintain a stable copper level in a quarantine tank utilizing these items however copper can be removed from these and they can be reused again in a full blown reef with inverts and corals including sps but the process is time consuming and somewhat expensive.

 

[zombie]

Just dump the basin and refill with fresh RODI. Any amount of copper left in the basin will be so insignificantly tiny there is no reason to worry about it. If you want to play it unreasonably safe, just run some activated carbon in the tank and remove it in a week.

You might be an engineer if...You have no life and can prove it mathematically.

 

[timnem70]

Over analyzed. Just dump, refill and as Irish says, if concerned run carbon. You'll be fine.

Sent from my LG-LS997 using Tapatalk

 

[jda123]

Copper takes so many forms. Some will get skimmed out attached to organics. All will bind with aragonite and not affect anything. It is one of the most overanalyzed and over-blamed non-issue for most tanks.

In most tanks with substrate, you would have to overdose copper to harm any inverts for long... it is mitigated very quickly in the rock and sand (that I would not recommend that you reuse if there is much bound to it). This is why copper tanks have nothing in them but water and fish and usually no skimmer.

Don't sweat this.