I keep my concentrated solutions in Igloo insulated jugs. The ones with the spout for easy pouring.
Also need to keep them in a darkened area otherwise algae will start growing in the nutrient and the calcium nitrate solutions.
The magnisium sulfate solution is not affected by algae for some reason.

Well i have a gallon of both parts of my nutrient solution (2 part) left over because i'm gonna try and run a small hydro set-up. I decided to put the parts in 2 seperate milk jugs and put them in the fridge, i am assuming this should keep the nutes for a while. Thanks for the reply.

-Curtis

I think as long as the temperature drop does not result in precipitation you should be fine.

what would happen if precipitation formed?

-Curtis

Basically what "drops out of" solution will not be available to the plant.

The saying "solubility varies directly with temperature" is mostly true.
In other words as temperature increased the solution can hold more dissolved solids.
Of course the reverse is true as the temperature drops there is a point where the solid can no longer maintain itself in solution and "precipitates" out.

Like all things in life there are exceptions. I believe Li2SO4 is a salt that buck that trend, but I don't believe it's used in hydroponics.

Hope this helps.

Oh yeah well i have it stored in milk jug's so i will warm up the solution from the fridge temp. when i decide to use it. I belive the solution may be super saturated now though.

I remember learning in chem that if you heat a liquid and dissolve a solid in it then cool it rapidly it will be able to hold more "solid" in suspension than if it where cooled at a slow rate which would allow the solid to settle out.

-Curtis

Yep that's called a "supersaturated" state and is very unstable.

A physical state change or even a physical shock could cause a cascade to equilibrium.