Oh yeah, I forgot that. When I said see if the liquid is discolored, that's another indication that you might need to flush. You SHOULD measure ppms in a soilless mix, but usually if the pH is correct and you see lockout/scorch symptoms, you can tell that you need to flush. Most soil growers don't have EC meters. I've TASTED my runoff before to determine salt buildup- it definitely has a flavor all its own- salty, yet metallic! A fine vintage! :wtf: