Better than that, i think it's 20ML per 10L of water, so 1 litre does last ages. But when you need to fork out $150 for a 20L drum of the stuff, you need to find some mates to sell it to.
The 20L drum says "add 20ml to 10L of cold or warm water to sanitize"
Without others to split the drum the expense is too high ($140). Between a few of us we split most of it up. I still have an extra 2L but someone else in Brisbane might want some next time.
I cleaned the outside of my keg last night and got very good results.
I removed the stickers and gluey crud with a razor and "De-Solv-it" , then gave it a scrub with a nylon scourer and "Gumption" , and then a polish with "Rubbedin Metal Magic" .
Three very strangly named products, but the keg looks great.
Not sure how long it lasts or whether it breaks down as such. Being an acid i think it would last for a long time, and would only be useless when the acid is exhausted.
I will look into it all.
I diluted 200ml into 1L so now I use it at a rate of 100ml per 10L