http://i.imgur.com/EC2iDu9.jpg
I'm thinking about getting one of these pH pens, probably the middle model. I have a distaste for the pH testing kits I've gotten in the past. Does anyone use these? What do you guys think, a waste of money? They also have a salinity pen which looks cool but is $60.
I'm thinking about getting one of these pH pens, probably the middle model. I have a distaste for the pH testing kits I've gotten in the past. Does anyone use these? What do you guys think, a waste of money? They also have a salinity pen which looks cool but is $60.


