Here is a question for you gurus.

Last year I was having problem with my clearing agent and water, I was getting scum (white deposits) on final prints even after proper wash.

It was suggested here ( thank you) to add Sodium Hexametaphosphate to my Sodium Sulfite.

the scum problem went away immediately.

What I notice is when mixing Sodium Hexametaphosphate it hardens like toffee and takes quite awhile to melt away.
I am using 2 litres of hot water , 10 grams SH and 200 grams Sodium sulfate .

Then I am adding 8 litres of 70 degree of water to make my working solution.

Why is the SH Clumping and going to this toffee like state. Am I mixing it too hot?? 120 degrees.