Blue/Green solution whilst using Oxy to clean plate chiller

[dcq1974]

Hi Brewsters
Just noticed the water colour change from clear/colourless to a turquoise/blue/green water whilst using Whizz Oxy cleaner in hot water to recirculate through my plate chiller...
Any ideas? I'm guessing it involves a copper complex of some form but has anyone noticed this before?

I'd previously cleaned my boiler/elements with Citric acid solution prior to adding the Oxy and recirculating..

Cheers

[phil.dadd]

It would be the acid then. I've had it when I've left starsan in mine a bit too long (like half an hour). The acid reacts with the copper or something...

[dcq1974]

I also didn't mention that I have a Garth/Aleman type hop stopper in the boiler. Although the mesh is stainless - all the other fittings are copper.
Came up really sparkly afterwards

I was more concerned that I wasn't stripping away any of the welding of the plate chiller??

[jack_c]

I guess copper chloride http://en.m.wikipedia.org/wiki/Copper(II)_chloride Whether it was the citric acid or the hydrogen peroxide from the oxy - no idea. Unless the chiller welds are copper, it probably just the chiller itself corroding

[phil.dadd]

They're normally copper braised stainless I think, so you're slowly stripping the copper. It would probably take longer that you would care to damage it though...