Nutrient Mixing Calculator
Take the guesswork out of feeding your hydroponic system. Our free Nutrient Mixing Calculator lets you determine the exact amount of concentrate needed for your reservoir based on your feed chart and plant growth stage. Perfect for beginners and experienced growers alike, this tool helps maintain stable EC levels, prevent nutrient burn, and reduce wasted solution—keeping your plants healthy and your system efficient.
Nutrient Mixing Calculator
Precision dosing based on chart scaling or target electrical conductivity.
🧪 How to Use the Nutrient Mixing Calculator
Whether you are starting a fresh reservoir or precision-tuning an existing one, follow these steps to get the perfect concentration every time.
1. Enter Your Reservoir Size
Type in the total amount of water your system holds (in Gallons).
- Don’t know? Most tabletop gardens (like LetPot or AeroGarden) hold about 1 to 1.5 Gallons. A standard 5-gallon bucket system usually holds 4 Gallons of actual water to allow for air space.
2. Enter Your Start EC
This represents the mineral content already in your water.
- If you don’t have a meter: Leave this at the default 0.5. This is the average “base” for most tap water.
- If using Distilled/RO water: Change this to 0.0.
- If topping off an old tank: Enter the reading currently shown on your EC pen.
3. Choose Your Mixing Method
Select your preferred level of precision from the dropdown menu:
Method A: Chart Scaling (%)
Best for beginners using the manufacturer’s feeding schedule.
- Check Your Bottle: Look at the chart on your nutrient bottle. Enter the mL per Gallon it recommends for your current stage.
- Choose Strength: Select a percentage based on your plant’s needs.
- 100% (Full): For established, heavy-feeding plants like tomatoes or peppers.
- 50% (Half): Recommended for leafy greens (lettuce, herbs) and young plants.
- 30% (Seedling): For brand-new sprouts just starting to grow.
Method B: EC Targeting (Precision)
Best for advanced growers aiming for a specific saturation level.
- Set Target EC: Enter the final EC value you want to achieve (e.g., 1.8 for Flowering).
- Enter Chart Dose: Provide the “Full Strength” mL/G from your bottle. The tool will use this as a reference to calculate the exact dose needed to bridge the gap between your Start EC and Target EC.
4. Calculate and Mix!
Click Calculate Dose. The tool will provide the required amount in mL and teaspoons.
Pro Tip: If using a “Multi-Part” nutrient (like a Flora Series Part A & B), the calculated dose represents the amount for each part. Always stir the first part into the water thoroughly before adding the second to prevent “lockout” or precipitation.
💡 Expert Tip: Always add your nutrients to the water one at a time. Stir thoroughly between “Part A” and “Part B” to prevent the minerals from “locking out” and turning into white flakes at the bottom of your tank.
More Hydroponic Tools
Use these tools together to dial in a complete grow environment. Each one solves a different piece of your system so you can move from guessing to precise control.
Core Nutrient Management
These tools control feeding strength and nutrient balance in your reservoir.
- Nutrient Mixing Calculator — calculate exact nutrient dosing based on EC targets, reservoir size, and growth stage
- EC to PPM Converter — instantly convert EC readings into all major PPM scales (500, 650, 700)
- Reservoir Top Off Calculator — fix nutrient spikes by calculating exact dilution water needed
- Hydroponic pH Calculator — Dosage and Drift Analysis — estimate how much pH Up or pH Down to add, and analyze long-term pH drift patterns to diagnose unstable reservoirs
Environment & Climate Control
These tools help you stabilize temperature, humidity, and plant stress levels.
- VPD Calculator — dial in ideal vapor pressure deficit for optimal transpiration and growth
- Grow Light Distance Calculator — set safe and effective light hanging heights based on wattage and plant stage
System Design & Setup
Plan your grow space before you commit to equipment.
- Hydroponic System Selector Tool — choose the best recommended system for you based on type and desired size
Diagnosis & Troubleshooting
When something’s wrong and you’re not sure why, start here.
- Hydroponic Plant Symptom Checker — work through nutrient deficiencies, root problems, pests, disease, and environmental causes from a plant’s symptoms
How to Use These Tools Together
Most growers don’t fail because of one mistake — they fail because multiple variables are out of balance. A simple workflow:
- Start with the Hydroponic System Selector to choose your setup
- Use the Light Distance Calculator to set your canopy intensity
- Dial in environment using the VPD Calculator
- Balance feeding with the Nutrient Mixing and EC to PPM tools
- Correct issues with Reservoir Top Off when EC drifts
- When something still looks off despite dialed-in EC, pH, and environment, use the Hydroponic Plant Symptom Checker to work out whether it’s a deficiency, a root issue, a pest, or disease
Need the full system? Access all calculators, selectors, and environment tools in one place on the Hydroponic Calculators and Tools page.