Well, it's Hulda Clark 's recipe. But is it for 5% Lugol's or higher?
If it's for 5%, then for 10g of I2 in the mix I will need about 227ml of water.

Okay, this page gives a formula, which basically confirms 5%/10%/85% proportion...

From: http://www.remedyspot.com/showthread.php/1552680-Homemade-Lugol-s-recipes


To make a 10% solution (can be used for 5%)
"Proof that the 10% Lugols solution described above is truly 10%:

16.9 gr/(16.9 gr + 33.7 gr + 118 ml) = 0.10 or (10 %) A similar calculation
can be performed for the strong Iodine tincture."