Well if you only buy a Ph meter how are you going to monitor the PPM then. That takes another meter. You can buy a 4 in 1 that does PPM, Ph, temperature, & EC all in one meter from Hanna. They cost about 150.00 or so and you can find them at most grow shops.

It's an important tool and if you are going to spend the money you should get a good one.

Don't forget the calibration solution too for TDS & PH.