JayWilly
Active member
I've owed a few ph pens in the past including bluelab , 2 differnt hanna and I've always had trouble with them staying in calibration so I gave them away and switched to ph liquid for along time well one day I got fed up with the time consuming practice of using ph liquid and decided to buy another pen to try out so I bought the YINMIK 2nd Generation ph and tds pen kit off amazon for 20.00. Thats 2 pens for 20.00 i couldnt beat the deal i said if they suck who cares its only 20.00. Anyways they are quality pens that are very accurate and stay calibrated for along time and are super easy to calibrate compared to my previous pens. I would definitely recommend them and if these ever fail I'm buying the same ones agian.
