hey anybody know bout some hydro.

you will prob never use up just down that just my opinion my up was a waste of money

Yeah, a pH of 7.2 will cause problems like you are experiencing with lockout. Definitely need to bring that down if you expect the plants to survive.

If you can only buy one, get the pH down. In case you overshoot your pH target by going lower than 5.5, you can always add more fresh water to increase the pH.