Water Quality Monitoring Imhoff Cone $247.57 Sludge Judge $602.76 Waterproof pH Tester 10 $326.30 Dissolved Oxygen Test Kit $400.40 Dissolved Oxygen Test Refills (30 Pack) $241.33 Dissolved Oxygen Meter $1,767.48 Septic System Revitaliser 1L $63.23 Septic System Revitaliser 5L $228.16 Turbidity Tube $178.33