Even decaffinated tea has some caffeine in it, which is terrible for dehydration.
Salt doesn’t have all the necessary electrolytes that someone with a j-pouch needs. You can purchase all different types of electrolytes to put in your drink or take by mouth, like drops, or capsules.
I myself use -GU Roctane Electrolyte capsules and drink electrolyte beverages.
I used to live in Florida, the heat was unbearable for me living with a jpouch.