High zinc on ICP

[ReefRookie22]

Hi,
Just got the results of my ICP and my zinc levels are 13.65ug/l (says ideal is 1.96ug/l).
Any ideas what could cause this?
Copper is undetectable so does that mean it's less likely it's rust?
I occasionally use metal tweezers but never have them in the tank for more than the time it takes to retrieve a coral frag.
Power head is only 1 year old. Filter and skimmer about 6 months that old.
Anything I can do except large water changes?

 

[Tikki]

Cuprisorb will remove zinc. I’ve been chasing zinc in my system for months. Was it present in your rodi sample?

 

[Randy Holmes-Farley Verified Community Expert]

Zinc often comes from metal parts (screws dropped in the water, hose clamps, etc.), but can come from plastics.

Is the tank apparently suffering?

Are you currently doing ordinary water changes?

 

[ReefRookie22]

Cuprisorb will remove zinc. I’ve been chasing zinc in my system for months. Was it present in your rodi sample?

I only did an ICP on my tank water.

 

[ReefRookie22]

Zinc often comes from metal parts (screws dropped in the water, hose clamps, etc.), but can come from plastics.

Is the tank apparently suffering?

Are you currently doing ordinary water changes?

The only potential sources of metal would be my filter, skimmer or power head but all are relatively new.
Tank looks fine tho have lost a couple of coral frags in the last few months but could have been anything.
I did notice my RODI went up to 1 TDS recently so I've changed my DI resin. Usually do 20% water change every 2 weeks or so.

 

[Randy Holmes-Farley Verified Community Expert]

Might be an unknown metal part fell into the tank, or a plastic that has zinc in it. Could be an additive.

What chemicals do you add to the tank?

Binders can work, but they also bind things you want, so are not a perfect solution.

 

[ReefRookie22]

Might be an unknown metal part fell into the tank, or a plastic that has zinc in it. Could be an additive.

What chemicals do you add to the tank?

Binders can work, but they also bind things you want, so are not a perfect solution.

I dose all for reef. I've used Aquaforest Mg and Ca at times. I use a tablespoon of activated Carbon and teaspoon of GFO in a media bag. That's about it.
I feed frozen mysis and Hikari S pellets.
I have dosed phytoplankton in the past not not as much lately.
Is there any way of knowing which plastics might contribute zinc?

 

[Randy Holmes-Farley Verified Community Expert]

Is there any way of knowing which plastics might contribute zinc?

Unfortunately, no. PVC is noted as a significant use, but lots of folks, including me, use plenty of PVC without elevated zinc.

I do not think it is especially common or problematic in general, but it some cases it may be. These companies talk about it:

https://www.zochem.com/advanced-zinc-oxide-for-the-plastics-industry/
https://www.nimbasia.com/blogs/what...izers-its-benefits-side-effects-and-uses.html