I having trouble mixing the "B" solution. I keep ending up with what appears to be an unmixed solution. I talked with the Photographers Formulary and was given advice about mixing the Potassium Carbonate to quickly. So I tried another batch mixing it much slower. However, I ended up with a milky looking stock solution. When it sits for a while it separates. I've tried mixing at both 68 degrees and 100 degrees. Same result. Can anyone help?