Electronic Meter PH for aquariums
This unit I bought with my TDS meter www.dx.com between the two cost me about 20 euros and am very happy with them because they work perfectly.
Make a good measurement of the main parameters of the aquarium should be something we practice regularly.
I home I have a few aquariums, so stick to measure and draw is very important and I do it with this device super fast.
I encourage everyone, works perfect.