Hanna
 
Grow Check pH meter continuous readout / wall mountable $99.95
Grow Check TDS meter continuous readout / wall mountable $79.95
TDS pen $74.95

 

Oakton

Waterproof (O ring sealed) pens that will actually float if accidentally dropped into a reservoir.

 
pH Tester 1 pen $94.95
pH Tester 2 pen $119.95
pH Tester 1 replacement electrode $44.95
pH Tester 2 replacement electrode $54.95
TDS Tester pen $105.95
TDS Tester pen replacement electrode $54.95

 

Other Suppliers
 
Dipstick nutrient TDS meter $109.95
Nutra-Dip TDS meter - continuous readout / wall mountable $86.95
American Marine pH meter - continuous readout / wall mountable $109.95

 

Accessories
 
Digital test pen batteries (pack of 4) $6.95
Electrode cleaning solution - 250 ml each of part A and B $10.45
pH 4 Calibration solution - 16 oz. $9.95
pH 7 Calibration solution - 16 oz. $9.95
TDS 1000 PPM Calibration solution - 16 oz. $9.95
Electrode storage solution - 8 oz. $6.95
Electrode storage bottle (fits Oakton pH pens) $2.95
pH test kit (color comparison) $6.95
pH test strips 4.5 - 7.5 $6.25
pH test strips 5.6 - 6.8 $6.56

 

pH Adjustment
 
General Hydroponics pH up - pint (8 oz.) $7.95
General Hydroponics pH down - pint (8 oz.) $7.95
General Hydroponics pH up - quart (32 oz) $12.95
General Hydroponics pH down - quart (32 oz) $12.95
General Hydroponics pH up - gallon $29.95
General Hydroponics pH down - gallon $29.95
Earth Juice Natural down (citric acid) - 2 lb. $10.95

 

For Soil & Soilless mixes
 
Rapidtest soil test kit $13.95
Moisture meter $5.95
Soil pH analyzer (analog readout) $32.95
Soil pH meter (analog readout) $17.15
Fine dolomite lime - 5 lb. $2.55
Fine dolomite lime - 40 lb. $12.95