Fill your trashcan with RO
water. Drop in there a 100W heater and a pump or pumps. Bring the water up to temperature. Start sifting in the saltmix. I use a small plastic container like a 2 cup measuring cup to sift/shake the salt into the water. After adding the approx correct amount to get the desired specific gravity drop in an airstone and let airrate for 24hours. After 24 hours verify the SG
. If its to low then add more salt. If its to high then add more RO
to balance it out.
I cant tell you how much salt I add because my cup I use I dont know what its measured volume is.