The Media Utilized in Hydroponics:
Many types of media can be used in hydroponics.
The most popular are:
Rockwool-rock
is melted down and spun into fibers. These fibers are then compressed into
cubes and blocks.
Perlite-
rock is heated and puffed like popcorn, resulting in small white pebbles.
Lecca
Stones- molten lava rock is formed into small
pebbles, that are usually red in color and very porous.
Vermiculite-
rock that is mined and used in some soil mixes. Small shale like pieces are
the result.
The main ideas behind any hydroponic medium is that it is inert, sterile, provides aeration, drainage and anchors the plant.
Hydroponics may also use no media at all. Rather
the roots may be suspended in water or air.