ProTeam Polyquat 60 and copper?

smohun

Active member
May 18, 2017
27
Leonardtown, MD
Hi. I've been adding some proteam every few weeks at the advice of the person who services my pool, in an effort to avoid some possible black algae. It seems as though every time I add it, I get a black ring in my skimmers. I also take my water twice monthly to the pool store for a sanity check and it shows copper (.4/.5) . I've looked everywhere and I don't see that polyquat 60 contains copper, but am I missing something? Thanks in advance!
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
16,104
Tucson, AZ
There is no copper in PQ-60. The black ring may be unrelated to metals. PQ-60 acts as a mild clarifier as well as an algaecide. So it could be that your skimmer is just getting a lot more gunk in it and it's leaving stains on the plastic skimmer wall. White PVC tends to develop dark discolorations over time from the buildup of scum and oxidation of chlorine. Try rubbing the black ring with a Mr. Clean Magic Eraser sponge and see if it comes off.

Are you on a well or municipal water? East Coast water supplies sometimes have copper in them and it's not unusual to find copper contamination in either well water or city water. If you are refilling from a source that has some copper in it, it will build up over time and concentrate as you add more and more fill water to compensate for evaporative loss. Honestly, I very much questions pool store metal testing as they are not very careful about it. If you had high copper levels and it caused scaling, you would see brown patches all over your white plaster and they would get considerable darker if you exposed them to ascorbic acid.
 

smohun

Active member
May 18, 2017
27
Leonardtown, MD
There is no copper in PQ-60. The black ring may be unrelated to metals. PQ-60 acts as a mild clarifier as well as an algaecide. So it could be that your skimmer is just getting a lot more gunk in it and it's leaving stains on the plastic skimmer wall. White PVC tends to develop dark discolorations over time from the buildup of scum and oxidation of chlorine. Try rubbing the black ring with a Mr. Clean Magic Eraser sponge and see if it comes off.

Are you on a well or municipal water? East Coast water supplies sometimes have copper in them and it's not unusual to find copper contamination in either well water or city water. If you are refilling from a source that has some copper in it, it will build up over time and concentrate as you add more and more fill water to compensate for evaporative loss. Honestly, I very much questions pool store metal testing as they are not very careful about it. If you had high copper levels and it caused scaling, you would see brown patches all over your white plaster and they would get considerable darker if you exposed them to ascorbic acid.

Thanks for all of the very helpful info. The black ring comes off easily, but it's just suspect that it happens after adding the PQ60. I have municipal water which tested negatively for copper in the past, but maybe that has changed. I wonder if it's the pool store's method of testing, since nothing else has been added to the pool. I will look into a test that I can administer myself. Thank you for all of the useful information.