Hey brother,
@Dothraki what media are you in?
And can you link your local water report or screenshot shot and remove info youd rather not share like general location?
0.5 is getting up there but there is a chance it could still be good.
In the meantime read this on PH. If in soil then imo you have no need to ph adjust other than for the purpose of mixing nutrients. The soil will buffer the PH.
In this article, we discuss proper pH levels for your weed plants; alkalinity, soil pH, tap water, and the effects of nutrients on pH when growing marijuana
www.thcfarmer.com