I do 2 teaspoon per gallon didn't want to make it any stronger.
55 gallon elephant nose tank.
30 gallon boraras ,bamboo shrimp, crs,rcs and different snails.
Unfortunately too low to be much more than a tonic. Need to get it to 1 to 3%. Neons I had at 0.3% in tank so in general I find fish can handle more than we think. If dosing in tank, I lift salt gradually. In dips, it seems to be remove when fish rolls over / too agitated.
http://www.theaquariumwiki.com/Salt