Small Particles Sand & White color particles from dispersion screen group head & in water

Small white & sand ( or slightly salmon or pink) color particles are dispensed in the water from the group head & dispersion screen when making coffee & or dispensing water for tea. I have ran water through this the machine so many times cleaned the screen etc., A smaller amount of the particles are dark. The particles are very fine & small in size. What is this? What is the problem?

Very Respectfully

James