People will tell you all sorts of things, IMO that is crazy high that is like deadly high, unless that's the value using tap water and after calmag addition etc.
I try to stick to the manufacturers recomendation and then just increase/decrease according to what my plants tell me, but there are some good Calculators out there for this sort of thing like this one from Canna:
www.cannagardening.com
Contrary to popular forum belief WATER is more important to your plants then their Fertilizer and a lot of people go way harder then they need to (with nutrient makers grinning ear to ear as they take your money).