My first grow I used the drops and did just fine. It's better than nothing. If you know someone with a meter you can tune in closer. My brother was going to hydro and wasn't going to check at all with drops. His PH was 7.5 and about dead . I tuned him in with my meter but I bet he still doesn't check, he is a soil man. His stuff always taste better, yea right. This year mine was sweet and his tasted like dirt and nutes. As long as you try to keep it close you will do alright. How about your EC, or PPM's ? How do you manage them ? If you go by the GH chart in the FAQ's page you can do good without a meter. I had a couple cheap meters that quit on me, now I have a Hanna that does temp,PPM,EC and PH. It's great and was a little over 150 bucks. If you get a meter don't forget the calibration solutions to check it. they can get out of cal too.