How do I build water level indicators for hydroculture pots?
I need water level indicators in opaque planting pots filled with LECA (Light Expanded Clay Aggregate) growing medium. The indicator needs to sit down in the LECA to the bottom of the pot with an indicator above the LECA to show how much water is in the bottom and non-viewable portion of the pot. The indicator can be a simple rise and fall system or even electronic, so long as it is low profile and does not harm the plant. The pots are different sizes, so I need a way to make the unit in various heights. Water levels I need to measure include a max level that varies per pot, a low level at about 1/4 or 1/2 an inch of water, and empty. Something that will look nice and not take away from the beauty of the plant is desirable, but functionality is the most important aspect of this project.
Hydroculture is also known as static hydroponics. The LECA I am using is Hydroton. With Hydroculture, plants are grown without soil. The Hydroton provides water and nutrients to the plant roots via capillary action and it is important that the maximum water level is just below the roots. The roots are not submerged in hydroculture like they are in hydroponics.
Give me your best ideas, creators!