Water Quality Analyzer

Enter your source-water test and get a clear read on whether it's good for irrigation: salinity, alkalinity, sodium hazard, hardness, and ion toxicities, turned into a treatment plan.

About this tool: reading an irrigation water test
About this tool: reading an irrigation water test

pH is not the number that matters. Alkalinity is.

pH is how acidic the water is right now. Alkalinity is how much acid it takes to change that, and it is what shifts your substrate pH over a season. Water at pH 8.0 with 30 ppm alkalinity is easy to correct; pH 7.2 with 300 ppm drives your medium alkaline anyway. 1 meq/L = 50 ppm CaCO3.

How strict your target should be

Depends on the buffer between water and root. Field soil is enormous, a plug tray is almost none.

SituationTarget alkalinity
Lawn and turf on field soilunder about 180 ppm
General irrigation, in-groundunder about 120 ppm
Greenhouse, containers, seedlingsunder about 80 ppm
Hydroponics and sensitive cropsunder about 50 ppm

Every acid brings something with it

Sulphuric adds sulphur, phosphoric adds a lot of phosphorus, nitric adds nitrate. Subtract it from your feed. Acid into water, never the reverse. Leave some alkalinity: zero means no buffer and a pH that swings.

Sodium is a soil problem

SAR compares sodium against the calcium and magnesium that hold soil aggregates together. High-SAR water disperses clay and seals the surface, so the ground stops taking water. Above about 3 warrants attention. Gypsum supplies calcium to displace the sodium.

Also worth checking

Boron has the narrowest safe range on the report: about 0.75 ppm for sensitive crops. And softeners swap calcium for sodium, which makes softened water worse for irrigation than the hard water it replaced.