do you have stagnent water somewhere near your grow? small flying insects love stagnent water to use as a breeding ground
White Flies
White flies behave just like spider mites. The insect hides underneath the leaf, and sucks it's dinner from it. Which results in white spots on the top side of the leaf. White flies are easily spotted with the naked eye. If you shake the plant a little, they'll fly around. They look like little white moths, around 2 millimeters in size.
Solution: ·A white fly problem can be solved by misting your plants in a solution made of 1 part SM90, 5 parts water. When you spray the plants, and make sure you get the undersides(that's where they lay eggs). You'll want to do this when the lights are about to go off(or else the leaves will get burned).
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Thrips
Thrips are small, fast-moving insects with wings. They rasp, or grate the marijuana leaves open, and suck the sap out. Thrips prefer flowering tops, and fresh, young leaves. Affected leaves have shiny, silvery spots. This is caused by the thrips sucking the chlorophyll out of the leaves. In spite of the fact that they're small, you can see them marching in columns on an infested plant.
Solution: Thrips can be fought with your favorite insecticide. Or predatory insects, the thrips' natural enemy is Amblyseius cucumeris.
amblyseius cuccmeris
http://www.biconet.com/biocontrol/cucumeris.html
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