When i clone in rockwool I will add a 1/4 tsp/Gal of calmag, 1 drop per gal of grower secret or superthrive, and .5 ml/gal of roots exel ph'd to 5.6-5.8. I use this mix for rockwool, rapid rooters, and peat moss cubes and it gives my great results in all applications.
That sounds right but you can go to grodan’s website and they lay it out for you. Peace sdd420