I have found that the green algae will slow down growth a little. If you add a little Algaefix (found at just about any store that sells fish, like petco) Totally safe and works wonderfully. To stop the algae use a panda-film cover over your tray or panda-film squares over the rock wool
The reason your getting algae on the tray isnt because of the system. Its because light penetrates through the plants to the tray and then algae forms when it can see that light. Its a tall-tale sign that you need a thicker canopy (aka more veg time, or more plants per tray). Never flood above rock wool cubes either, flood em till they are an inch from the top of the cube.
yes just what he said it doesnt hurt your plant it just slows growth because the algae sucks up the nutrients so therefor your plants are lacking nutes
(basically its like taking food away from you right when your about to take a bite).....LoL
Exactly. The panda film is used to keep the roots in the dark and also reflects light back up to the lower branches. I use it in both my mid-growth clone tray and my full sized tables.
And i jsut buy it at my hydro store? never seen it... i will have to ask, but i know what your talking about. THats what i have covering my cube tops now.