Used Dishwasher Cleaning Issue

[wishywashy]

I've just purchased a second user dishwasher as it was barely used.
The unit is in perfect condition however the salt chamber when opened there was some thick white bits coming out collected chunks of scum and other bits.
I've run a hottest setting cycle and will run a few more I've tried to clean inside with anything that will reach but is it safe to use? I'm not sure how the salt chamber is shaped so what's the best method to ensure its cleaned out and sanitised other than dismantling.. I'm not electrical or plumb minded so way over my head
Thanks

 

[James]

Get a bag of dishwasher salt and fill it to the top.
it is supposed to be full of water and “white lumps” aka salt.

 

[wishywashy]

No the chunks are like scum, like fragments and thin strips of egg white.
My guess is that the water went stagnant I'm it.