Okay, one for the brains trust.
When I was taking Galini up the coast for the first time, we discovered that the water system needed some attention. So the water bladder is currently at home and I'm soon to replace all the plumbing. (fortunately there isn't a huge amount of it)
Anyway, ran tap water through the bladder several times, water is clean. Took the bladder out of its cover to hang up and discovered brown slime inside the bladder (photo hopefully attached).
Any suggestions for cleaning this, I've tried flipping it inside out which didn't work - my next thought was puratabs but that will only make the water safe to drink, not solve the problem.
So I figured I can't be the first person with this problem and thought I'd ask for your advice.
Here is the (bad) photo: