My Father, Aged 82 Years Having Pottasium Level 5.8, Creatinine

My father, aged 82 years having Pottasium level 5.8, Creatinine 1.8 and asked K-Bind 1 Sachet thrice a day for 3 days and after that repeat Blood test to do. I want to the water quantity for mixing the powder and should be taken immediately after meal or anytime. Please answer.