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.
Want to streamline your entire hydroponic setup? Don’t forget to check out our other essential tools:
The EC to PPM Converter for accurate nutrient readings,
the Hydroponic Light Distance Calculator for optimal lighting,
the Reservoir Top Off Calculator Use this after mixing your nutrients to maintain the perfect balance. It calculates the exact amount of fresh water needed to fix EC spikes as your plants drink throughout the week.
the Hydroponic System Selector Tool to find the best setup for your space.
Each tool is built around real-world growing practices to help you grow smarter, not harder.