Quite a number of folks have reported difficulty in mixing the B solution of Pyrocat-HD with the Formulary kit. Since I have never used this kit I don't actually know either exactly what is in there, nor the directions for mixing. Perhaps if you could send me a description of how the kit is packaged, and the directions for mixing, I could figure out the problem.
I have always mixed Pyrocat-HD from bulk chemicals and not from a kit, and when the potassium carbonate is added slowly to the water, as described in the article at www.unblinkingeye.com, I have never had a problem with getting the chemical into solution. And there should not be either, since potassium carbonate is soluble in water in percent solutions well over 120%, and one is nowhere near this figure when adding 100g of chemical to 100ml of water.
One of the mistakes that a number of people have made in the past is to attempt to mix the 100g of chemical in water to make 100ml of solution, but as someone points out further in this thread, the correct way to mix is to add 100g of chemical *slowly*, and with constant stirring, to 100ml of water, which will give a final total solution of around 125-35ml of B stock solution. Since slowly is a relative term I will qualify it for this context by saying that it should take no longer than about two minutes add the potassium carbonate to the water and have it completely in solution. And contrary to some recommendations I have seen, water at room temperature (70F or greater) has always worked fine for me.