Copper Level In Display Tank with Corals

[SinkyShippy]

I have a 22 gallon fish tank with a homemade AIO. It was cycled in November. It's been running since the beginning of December. It has two clownfish, two pipefish (they're expecting!), a randall's assessor basslet, and a court jester goby.

Recently my corals have been having issues. It started mid-March. I chalked it up to it being the salt since the Red Sea levels I've been getting were utter crap. I sent in samples of salt to them and they tested them and found out it was also off by a lot. Like to the point where they're sending my samples to Israel for additional testing.

I've been consistently checking the levels in my tank. I started checking copper the other day and noticed a residual (.07 - hanna copper tester) so I've been trying to address the issue with cuprisorb and polyfilter. I have never dosed copper in this tank. I also ran through the sand with my filters to see if I dropped any metal in, nothing.

I tested the RODI unit I have and that came back positive for copper as well as a level of 61 TDS so I swapped out everything in the RODI unit, which now has a level TDS of 0 and a copper level of 0. I work at a LFS part time so in the meantime I did a water change with their 0 tds/0 copper rodi water and my new brand of salt Nyos (since I didn't trust red sea anymore). Yesterday I tested the tank and it was .13 and today I tested the tank and it had a .37 residual so it went up since adding the cuprisorb, poly filter, and water change overnight which makes zero sense.

I went to do another water change today to bring down the copper level. I tested the saltwater batch with Nyos salt and that came back .27. I did a small batch with red sea salt and that came back .42.

I'm sort of at a loss here. I don't know how to deal with the copper. I don't know why my salt mixes are coming back positive for copper. Can anyone help?

 

[Randy Holmes-Farley Verified Community Expert]

The Hanna copper tester is unsuitable for this purpose and frequently reads levels when none shows by icp.

 

[SinkyShippy]

The Hanna copper tester is unsuitable for this purpose and frequently reads levels when none shows by icp.

So it's possible that the tank actually has 0 copper and I am just getting a false reading?

 

[Randy Holmes-Farley Verified Community Expert]

So it's possible that the tank actually has 0 copper and I am just getting a false reading?

Almost certainly that is the case.

This device is useful for medicating fish, but not checking levels in a normal reef.

 

[SinkyShippy]

Almost certainly that is the case.

This device is useful for medicating fish, but not checking levels in a normal reef.

Well that's the most relieving this I've read in the past month. Thank you.

 

[Randy Holmes-Farley Verified Community Expert]

If you want to diagnose if the coral issues are metal related, an icp test can be useful.

 

[SinkyShippy]

If you want to diagnose if the coral issues are metal related, an icp test can be useful.

Ok. Thanks a ton!

 

[SinkyShippy]

If you want to diagnose if the coral issues are metal related, an icp test can be useful.

You were right about everything. I picked up a Salifert copper test to have as a backup and everything tested negative for copper. Crazy. You’re the bomb, man.

 

[pgh94]

Thank you! This has been driving me crazy as well!