Holy crap. I've been using a no-name dishwasher powder - basically just alkaline salts - and I've been getting good results, or so I thought. That percarbonate stuff looks to be the shiznit.
Given that my LHBS are a bit of a rort with their prices *cough*brewcraft*cough*, can someone here recommend a supermarket product that contains sufficient percarbonate to do the job properly? Will no-name napisan cut the mustard in this case?