Solutions to calibrate your monitoring instruments.
pH 4.01, pH 7.0, 1500PPM
General Hydroponics uses the highest quality reference solutions, allowing growers to calibrate many popular brands of PH, EC and TDS meters (NaCl scale or the 442 scale). General Hydroponics technicians check each batch to ensure that our solutions are precisely calibrated and yield reliable readings each time they are used.
- 8 oz
- 1 Quart