Calculate Lucas Formula nutrient amounts for General Hydroponics Micro and Bloom: enter your water in gallons or liters to get the mL of each to add.

Measured solution EC
Optional. Enter a meter reading after mixing to convert it to the 500 ppm scale.

Related Calculators

Lucas Formula

The Lucas Formula is a simplified method for mixing hydroponic nutrients without the need for a separate Grow formula. The formula is based on the use of General Hydroponics Flora series and is as follows:

Micro Nutrients = Water Volume (US gallons) * 8 (ml)
Bloom Nutrients = Water Volume (US gallons) * 16 (ml)

Variables:

  • Micro Nutrients (ml) – The total volume of Micro concentrate for the selected water volume.
  • Bloom Nutrients (ml) – The total volume of Bloom concentrate for the selected water volume.
  • Water Volume (US gallons) – The total volume of water for which you are mixing nutrients.

To use the Lucas Formula, simply multiply the volume of water by the specified amounts of Micro and Bloom nutrients. No Grow nutrients are used in this formula.

What is the Lucas Formula?

The Lucas Formula is a hydroponic nutrient feeding strategy that simplifies the process of preparing nutrient solutions. It eliminates the need for a separate Grow nutrient and relies solely on Micro and Bloom nutrients. This method is popular among growers for its simplicity and effectiveness, especially for those using the General Hydroponics Flora series of nutrients.

How to Calculate Nutrient Amounts Using the Lucas Formula?

The following steps outline how to calculate the amount of nutrients needed using the Lucas Formula.

  1. First, determine the total volume of water you will be using (in gallons).
  2. Next, use the Lucas Formula to calculate the amount of Micro and Bloom nutrients needed.
  3. Finally, add Micro to fresh water and mix thoroughly, then add Bloom separately. Never mix concentrates together. Check pH and EC after mixing and follow the product label.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

Water Volume = 10 gallons

According to the Lucas Formula:

Micro Nutrients = 10 gallons * 8 ml/gallon = 80 ml

Bloom Nutrients = 10 gallons * 16 ml/gallon = 160 ml