gareth price wrote:
I've got a 3litre camelbak and forgot to clean it!! I've now got black
marks inside. I've done washing with hot soapy water and then milton
overnight inside the bag but the marks are still there. Any suggestions?
I've heard using denture tablets is a good one or are the camelbak cleaning
tablets any good?

Thanks

Gareth

Mechanical cleaning with a strip of cotton cloth of whatever size you
can get in through the opening, and just the right amount of water (a
small amount found by trial and error) was a very effective method for
cleaning algae from the inside of glass vessels in my lab days.

You need to devise a way of causing the cloth to rub the surface where
the marks are, and the amount of water is critical to achieve this.

Wash out thoroughly and sterilise with Milton.