Instruct: Classify the given Amazon review into its appropriate rating category
Query: Will not mix completely

It's good for electrolytes but hard to get it down. It will not completely dissolve. There is always a mixture in the bottom and is grainy when you try to swollow. I have shaken it until it looks mixed and it still won't dissolve. I shake it every time I take a sip of it. It still won't dissolve completely.