pH/EC Maintenance
- Active Air
- Essentials
- Active Aqua
- Blue Lab
- General Hydroponics
- Green Air
- Hanna Instruments
- HM Digital
- Milwaukee Instruments
- Nutradip
- Oakton
- Technaflora
- Thirsty Light
1000ppm Calibration Solution  $6.95 | 1382 PPM  $1.95 | 1382 TDS Solution $1.95 |
1500 ppm  $1.95 | 1500 ppm Calibration Solution  $8.20 | 3 function SM802  $229.95 |
Active Air 2-Way Meter $7.95 | Active Air 3-Way Meter $9.95 | AquaPro TDS/Temperature Meter  $44.95 |
Calibration Solution $1.78 | Calibration Solutions $23.95 | Champ pH Tester $58.95 |