Since you want the K-meta to mix, I suggest you put it into the bucket for bottling. I make a solution of ¼ tsp of K-meta to six ounces and store it in a plastic medicine bottle like the ones a pharmacy uses for cough syrup. Then for each gallon of wine you need one ounce. Since it is pres-dissolved, that aids in mixing.I have used two buckets in the past with spigots and both failed me the last time I made wine. They leaked! So, I bought something else I can’t recall from Label Peelers to fill bottles. I haven’t used it yet.
Do I put the K-meta into the carboy prior to racking or in the bucket prior to bottling.
I made kit wine before but after being on the forum I’ve become less confident !