EC ↔ PPM Converter
Convert nutrient EC to ppm across 442, 500 and 700 scales.
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Tools & Calculators
Every tool in one place. Search or pick a category, then start doing the math.
Indoor & Hydroponics — 18 calculators
New New Grow Light DLI Calculator
Daily light integral from PPFD and hours — and the runtime or intensity a crop needs.
Use ToolNew Grow Tent Circuit Breaker Calculator
How many grow lights, fans and pumps safely fit on a 15 A or 20 A circuit.
Use ToolNew Extension Cord Voltage Drop Calculator
Voltage lost along a garden or grow-room extension cord, by gauge, length and amps.
Use ToolNew Grow Light Run Cost Calculator
Monthly and yearly electricity cost to run a grow light, by watts, hours and rate.
Use ToolNew Grow Room Fan CFM Calculator
Exhaust fan size in CFM to exchange a grow tent or room's air on schedule.
Use ToolNew Hydroponic Reservoir Size Calculator
How many gallons of reservoir your hydroponic plants need, by crop and count.
Use ToolNew Nutrient Dose Calculator
How many mL of stock solution to dose a hydroponic reservoir up to your target ppm.
Use ToolNew Reservoir Correction Calculator
Fix a hydroponic reservoir already mixed: how much stock to raise it, or water to lower it, to a target ppm.
Use ToolNew Kratky Method Calculator
Reservoir size in gallons and liters for passive Kratky hydroponics, by crop and plant count, with a bucket count suggestion.
Use ToolNew CO2 Supplement Calculator
Grams of CO2 to lift a tent or room to target ppm, the ppm each gram buys, and how long a tank or burner supply lasts.
Use ToolNew Aquaponics Fish to Plant Ratio Calculator
Balance stock from grow-bed area: fish biomass, daily feed allowance, plants fed and minimum water volume by system type.
Use ToolNew VPD Calculator
Vapor pressure deficit from temperature and humidity using Tetens' equation, with stage-appropriate kPa verdicts for tents and rooms.
Use ToolNew Mushroom Substrate Calculator
Wet substrate weight, flush yield, pasteurization hours by method and a colonization finish date for a dry-weight recipe.
Use ToolNew Water Potential Calculator
Calculate solute and total water potential from the van 't Hoff relation, in bars, megapascals and psi, with a water-movement verdict.
Use ToolNew Aeroponics Misting Duty Cycle Calculator
Convert nozzle count, flow and timer on-off seconds into duty cycle, daily water, pump run hours and the root dry interval.
Use ToolNew Grow Tent Heat Load Calculator
Turn fixture wattage into BTU per hour, then size the exhaust that holds your temperature rise and check the fan you already own.
Use ToolNew Hydroponic System Cost Estimator
Price a hydroponic build as startup, power and nutrients per cycle, then compare the harvest against what the same food costs at the store.
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