Why would you not have to pH? Dont you use different strength nutes through out your grow?
I don't PH because the soil medium I use Pro Mix has a buffer in it. It handles it for me. I don't know the science behind it (Honestly) however I haven't PH for two crops now. I have no problem. I am still learning MC. I switched in the middle of my crops... I was scared but I got sound advice and went for it. Never looking back. Thankfully. Love this group