Your Grobo will automatically fill to the proper amount based on the stage of your recipe.


At different stages, your plant needs different amounts of water. When filling your Grobo, you will notice that it automatically stops at one of three water level sensors. 


Here are the three water level sensors, High, Middle, and Low.


  • High - Your plant is young and doesn't yet have the roots to reach water on its own.
  • Middle - Your plant is getting bigger and wants to stretch its roots to reach the water.
  • Low - When draining, you will notice that there is still water at the bottom of your Grobo. That's okay! It's designed this way to keep your pH probe wet.


Please DO NOT manually add water unless you see the water level is at the bottom sensor. Your Grobo knows what the water level should be, and manually adding water instead of doing a drain and fill will prevent the unit from dosing nutrients. You will receive notifications to drain and fill your unit, and sometimes to do a Top Up. This means your unit needs to be filled up slightly more to allow the plant to reach the water.


Still have questions? Please see HERE for how to contact us.