Blue water staining around rim of bath

[Glismore]

Hello, my customer has started to experience blue staining around the rim of the bath. PH reads 7.25 - normal for here. Harveys dualflow water softener installed. Un-vented DHW system. House is around 15 years old, no recent / new copper pipes fitted. All other piping is copper. I'm considering a number of possibilities (probably not exclusive) but am on the border of my knowledge

1. The sacrificial anode (if there is one) in the hot water tank requires replacement, or if electronic then the circuit may/may not be functioning (resulting in your copper pipes being eroded)

2. Earth leakage or other earthing issues in the electrical system causing the copper pipes to be used as alternative earth causing erosion

3. Excessive velocity in the water pipes dissolving the copper

4. Possible lack of di-electric connectors on some of the connections on the hot circuit allowing a “battery effect” to occur

Can anybody help here please. Has anybody got any other hints ? Thank you.

 

[ShaunCorbs]

They haven't used a blue bomb have they / them bath fuzz things

 

[Glismore]

They haven't used a blue bomb have they / them bath fuzz things

Hello Shaun Corbs , nope, nothing like that, no Radox etc. Some Epsom salts once a few months ago. It's a mystery so far.

 

[Stigster]

This is a document on copper corrosion in plumbing systems. http://www.fwr.org/copper.pdf

I have posted the link before but it makes for interesting reading if you like such things. Section two of the document talks about blue water. Can be caused by microbial action or the water company adding phosphates to help protect lead pipes in their network. Unless the pH of the water has taken a massive shift recently, I don't know what else would cause the water to change and start the blue corrosion you see there.

 

[ShaunCorbs]

This is a document on copper corrosion in plumbing systems. http://www.fwr.org/copper.pdf

I have posted the link before but it makes for interesting reading if you like such things. Section two of the document talks about blue water. Can be caused by microbial action or the water company adding phosphates to help protect lead pipes in their network. Unless the pH of the water has taken a massive shift recently, I don't know what else would cause the water to change and start the blue corrosion you see there.

It's too blue for that and I take it only happened in the bath???

 

[jtsplumbing]

How long has the water softener been installed ? is it the salt type ? if so could be an issue with unit, if new its cleaning the system and could take a few weeks to work

 

[Glismore]

This is a document on copper corrosion in plumbing systems. http://www.fwr.org/copper.pdf

I have posted the link before but it makes for interesting reading if you like such things. Section two of the document talks about blue water. Can be caused by microbial action or the water company adding phosphates to help protect lead pipes in their network. Unless the pH of the water has taken a massive shift recently, I don't know what else would cause the water to change and start the blue corrosion you see there.

Thank you Stigster. The Ph as measured is exactly the same as the latest yearly data from Thames Water. I'm not sure about phosphate.

 

[Glismore]

This is a document on copper corrosion in plumbing systems. http://www.fwr.org/copper.pdf

I have posted the link before but it makes for interesting reading if you like such things. Section two of the document talks about blue water. Can be caused by microbial action or the water company adding phosphates to help protect lead pipes in their network. Unless the pH of the water has taken a massive shift recently, I don't know what else would cause the water to change and start the blue corrosion you see there.

Thank you for the link to the article on copper. I was aware of most but not all of it so interesting reading.

 

[Glismore]

It's too blue for that and I take it only happened in the bath???

As far as can be made out it is only the bath that is being affected. No evidence of blue staining elsewhere. thankyou.

 

[neilrj]

I've seen this in many hot tubs and no idea of the (blue) cause but a biocide in the tub to clean the tubes sorted it really quickly - basically put the Jacuzzi on full for a bit with the biocide (chlorine/descaler/degreaser) and it'll strip any crud off the pipes that may be re-depositing at the bath tide mark. Incidentally hot-tubs when used by freshly showered guests never had this issue, it was only guests straight into hot tub 'dirty' with cosmetics/sun cream on that had festering water. I never use a hot tub or Jacuzzi anywhere without dip testing water (sad I know).

 

[Glismore]

I've seen this in many hot tubs and no idea of the (blue) cause but a biocide in the tub to clean the tubes sorted it really quickly - basically put the Jacuzzi on full for a bit with the biocide (chlorine/descaler/degreaser) and it'll strip any crud off the pipes that may be re-depositing at the bath tide mark. Incidentally hot-tubs when used by freshly showered guests never had this issue, it was only guests straight into hot tub 'dirty' with cosmetics/sun cream on that had festering water. I never use a hot tub or Jacuzzi anywhere without dip testing water (sad I know).

Thank you Neilrj. The single user of the Bath is an elderly lady. I will make discrete enquiries re makeup / lotions etc and see what chemicals are uncovered.

 

[oz-plumber]

Elderly Lady - Blue Rinse?

 

[marvoni]

........
2. Earth leakage or other earthing issues in the electrical system causing the copper pipes to be used as alternative earth causing erosion
.......

You only really get galvanic corrosion issues with DC leakage currents. Nearly all domestic electrical leakage, both functional leakage and fault currents, would by AC in nature and unlikely to cause problems with copper pipes.

The blue colour is mostly around the scum line so my thoughts are bacterial or maybe some chemical reaction between soaps, bath salts, general contamination from cosmetics etc and I shudder to think what else.

 

[Glismore]

Thank you for all your input. Will approach client delicately and see.