To clarify, I read your original post as meaning your nutes were mixed into water, and that's what I do in a tub including additives!!! I then add that to my reservoirs to top off!! I use hybrid areo and DWC and it is a pain in the ass to mix in them! I would be very careful about doing this or using mixed nutes not kept in the fridge!!! I do have mixed nutes in the fridge but never more than what I will use within a week!! Remember, I do not recommend any of the things I do regarding nute storage but I have not had any problems!!