This pen is offered in perfect working order. It’s 8-9 months old and is excellent. The VIVOSUN Digital PH Meter is a high accuracy pen-type tester specifically designed for hydroponics. This pH meter accurately measures the pH level of various water sources, making it suitable for use in hot tubs, koi ponds, fountains, aquariums, ponds, and swimming pools. With its advanced technology and precise measurements, this testing kit is essential for maintaining the ideal water conditions for a thriving environment.
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