The green slime you have on your
rockwool is called Algae. Photo
contributor Oldpink
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Algae needs light and nutrients to
live, it will spread to your reservoir and will block
feed lines. Because of rockwools unique vertical
'tube-like' structure, which takes up nutes via
capillary action, and pulls air into the medium as the
nutes drain outward, a heavy buildup of algae can
effectively block this breathing action. To prevent this
from happening, use light-proof and water-proof material
to cover your rockwool, for example black/white panda
film or thick black bin liners. |