I'm about to move into an apartment, and I'm playing with different ideas for reusing water so I'm not dumping a lot of water off my balcony where I'll be brewing.
One thing I'm thinking of is getting some type of plastic barrel and running my IC water into it, then using that water for the mash/sparge/boil next time I brew.
My question is, is there any problem with letting water sit in a food grade container outdoors for several weeks? I typically brew about 3 times a month, give or take.
I understand I'll lose some to evaporation, and this will alter the chemical composition a bit, but will it affect it very much if it's a closed container?