Absolutely!! I had been using Fox Farm nutrients and finally got completely fed up with them in the middle of a grow and just switched... nothing special to do - just switch the nutes when you next need to feed them... I was SO happy I had done that.... of course, I didn't like the nutes I switched to but they saved that particular grow. I'm now using the General Hydroponics FLora series and am VERY satisfied with everything... Thinking I'm going to have a yard sale of half-used nutes only! LOL!
Seriously - just switch to whatever you want... no harm, no foul...
Good luck!