How to mix platinum toner?

I want to mix a toner for Kallitypes, but want to be clear I have the right solutions. This is the toner formula I would like to use.

Citric acid 5g

Potassium chloroplatinite 20% solution 5ml

Water 1000ml

What I am questioning, is the 20% solution, and how to mix this. Is it 10ml water plus 2g of Potassium chloroplatinite( 2g/10ml=20%)?

Another formula I found uses this:

Citric acid 5g

Potassium chloroplatinite 0.5g

Sodium chloride 5g

Water 1000ml

I don't have Sodium chloride, can I use this toner formula without it?

Thanks for your help.

-Martin