P.S. -- I'm not 100% sure but I don't think 217 is a systemic pesticide. That means the chemical only stays on the surface instead of being absorbed by the plant therefore washing it with the water hose might have good results. However if 217 IS systemic then you might be screwed. Flushing might help get rid of a systemic pesticide, especially in a hydroponics system.
SNS 217 is not a"chemical" at all... its main active ingredient is pure rosemary oil extract, mixed with water, Polyglyceryl oleate, & lauric acid & it does not leave a chemical residue, they promote it being safe to use on edible crops. It is 100% organic.
from their site:
Uses
SNS-217 Spider Mite Control can be used on a wide variety of plants, vegetables, and even trees. When applying the product take caution not to spray any buds on the plant, in doing so this could result in burning the buds sprayed. SNS-217 Spider Mite Control can be sprayed on fruits, vegetables, and plants varying from; apples, apricots, beets, broccoli, cabbage, carrots, cauliflower, celery, cherries, chives, corn, cucumbers, peppers, tomatoes, parsley, fuchsia, roses, flowers, houseplants, etc.
SNS-217 is fully bio-degradable and is not toxic to animals and under directed normal use, should not affect the plant's metabolism.
It specifically says not to spray on "BUDS" (flowers) but.... if you spray everything right before lights off, DO NOT use a "wetting agent" & make sure to hit the undersides of the leaves, then respray with fresh water after 12 hrs, at lights on, turn your oscillating fans on after spraying fresh water to help evaporate what you've just sprayed
This should avoid most if not ALL flower & leaf burn. (next time)
-Tarzan