[jikwan]

ive taken to use RO water for my trad work  store it in a 25lit white plastic drum in my estate van   even after a week an alarming amount of algae has fomed around bottom of drum it is 001
my wfp DI 000 water i store outside partially covered but is still exposed to light im worried about  is algae forming there also?

[Jeff Brimble]

Good question about the DI water, I dont know if algae forms more. The alguy wont make any difference to your tds readings.