medium ph??

Hi all, I'm about to start my first grow and I've been gathering all information possible before starting. However the ph tester I have I'm guessing can only be used for water etc (a small tub with some solution, simply add afew drops and compare to the colour chart). Is it enough to just check the ph of my water and nutrients?? Or is it a must to check the medium aswell? I've been looking at the probe ph testers on the internet and found one with a soil moisture tester and light tester aswell for £8. Is it worth me buying this one so I can check medium and soil moisture aswell? As this could help me with the watering anyway as I'm very conscious of over/under watering which as I've heard is pretty common. Thanks for any advice in advance
Hmmf

P.s. Can a ph probe meter be used to accurately test the ph of the water/nutrients aswell or is it just for the grow medium?? Cheers hmmf

if it is 8 pounds, you are using the term probe liberally. There are expensive probes for liquids, but those cheap ones are for rough estimates on soil.

What is your medium? IMHO, with a good soil mix that has dolomite lime in it, if you religiously PH everything going in, you don't need to PH the soil.

But I would invest in a PH pen for the water and nute mixture. You don't want to have to mess with the with the drops thing. Major pain in the ass and not very accurate.

The color strips will sorta get you in the ball park.
You in soil? IMO- I would get a soil pH tester, there really cheap.
Or you can test the run-off water from your medium your using to grow.

The color strips are better than nothing, but your going to need to invest in a meter down the road,

Good Luck on Your Grow.

Cheers for the quick replies guys! I'm using coco for the growing medium. Can a pH pen be used for both the medium and liquids? If I test the run off water and the PH level is all out of whack, how would I go about adjusting the ph level throughout the medium without overwatering my girls? Again cheers for the advice, any input is much appreciated!