it appears to be a cal/mag def a larger pic may help fro 100% conformation,use sum salt now, and for the rest of your grow
i do believe there was sum +rep promised ahahha
1 tsp per gallon is fine and use good water with no more than 500 ppm in it if you don't have this use bottled water. add a drop of dish soap to the mix but don't get it on the buds. good luck