yes you can have a toxic levels of nutes

from what i have seen its hard to overdo potasium. potasium is essential for the plants health/immune system

another thing to look at is if you have some problems, it could be due to wrong ph ranges. nutes are available at different ph levels and if they are out of wack it can cause a lockout condition.

what is this stuff exactly, what's the npk value of it. little more info on it