Strange stains in caravan

[ten0rman]

Hi folks,

I'm looking for ideas on what may have caused some strange dark(ish) grey stains in the mugs and the kitchen sink of our caravan.

Caravan used 1st 2 weeks of June in Scottish Highlands - no problems at all.

Used again 1st 2 weeks of August in Gargrave (near Skipton in N. Yorks.) and a dark(ish) grey stain has appeared in our melamine mugs and in the kitchen sink. It is not apparent on any other plates/bowls (also melamine) nor has it appeared in the other sink, or in the shower unit (although the shower hasn't been used that much).

The mugs have been stained by the usual tea/coffee stains and cleaned with Puriclean as was the water system: in both instances this was before the June holiday.

One thought is that the Gargrave water is, I'm told, quite hard whilst the Scottish water I think is quite soft. But we've been to Gargrave before with no ill effects.

Another thought is that the same bottle of green Fairy washing up has been kept in the caravan for a few years now. Can it have deteriorated? In which case why aren't the plates & bowls stained?

Any thoughts?

ten0rman

[servodude]

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[MyNameIsUrl]

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[bionichamster]

Hi folks,

I'm looking for ideas on what may have caused some strange dark(ish) grey stains in the mugs and the kitchen sink of our caravan.

Caravan used 1st 2 weeks of June in Scottish Highlands - no problems at all.

Used again 1st 2 weeks of August in Gargrave (near Skipton in N. Yorks.) and a dark(ish) grey stain has appeared in our melamine mugs and in the kitchen sink. It is not apparent on any other plates/bowls (also melamine) nor has it appeared in the other sink, or in the shower unit (although the shower hasn't been used that much).

The mugs have been stained by the usual tea/coffee stains and cleaned with Puriclean as was the water system: in both instances this was before the June holiday.

One thought is that the Gargrave water is, I'm told, quite hard whilst the Scottish water I think is quite soft. But we've been to Gargrave before with no ill effects.

Another thought is that the same bottle of green Fairy washing up has been kept in the caravan for a few years now. Can it have deteriorated? In which case why aren't the plates & bowls stained?

Any thoughts?

ten0rman

Your are quite possibly on the right lines regarding the hard water.

Read this link https://blog.get-melamine.com/melamine-dinnerware-staining-and-how-to-avoid

Quote: “ Protein build up may be another issue many people will identify as staining but is actually caused by the minerals found in hard water. Protein build-up occurs during the dishwashing process when hard water minerals, specifically calcium and magnesium, combine with proteins left over from food and adhere to the melamine dinnerware. ”

BH