Saving Nutrient Water

Hello.

I have a 10 gallon tote DWC. I'm changing water once a week (changed to every 5 days), and every time I do, I end up having leftover nutrient solution.
I throw that away. About a gallon.

This time, I filled 4 1.5l drinking water bottles (not sterilized, used), and put them in the fridge.
Wondering is there any issue with using that water next time I change DWC water? Pathogens or nutrient degradation due to low fridge temperatures?

I can of course be more careful with how much water I mix, but just wondering.

Thanks

I just mix in my bin, no leftovers. I use a spare bin that I can mix the solution in, then just move the top, with the plant, into the new bin with fresh solution, then I go water the wife's flowerbeds and houseplants.

Not sure what effects just storing the solution would have. I'd think it would at least need mixing to prevent settling and possible fallout.

I've left nute solution sitting in a 5 gal bucket for over two weeks. No problem.
Just check ph & ppm before you use it. If everything is dialed in you can go two weeks between nute changes.

Ok thanks. Will use it next week then.