Should I worry or be concerned with the EC of my runoff? My feeds are following the chart at 3.0-3.1 EC and my runoff is at 4.7, should I flush my plants?

Measuring runoff EC can be very deceiving and not an accurate depiction of what is going on in the coco after you have replenished it. EC meters used when mixing your reservoir and some soil sensors measure bulk EC which is the EC of undisturbed water/soil. Good soil sensors measure pore water Ec which is the EC of the water stored in the pores of the medium that is actually available to the plant. As moisture levels raise within the coco the pore water EC will lower, while you'll see an increase in pore water EC as moisture levels drop. We typically aim to keep pore water EC in a 4-6 EC range with most strains or genetics after the refreshment irrigations. Chasing runoff EC typically creates issues that were nonexistent to begin with. Measure runoff pH to make sure it is staying between 5.4-6.4. Always gauge plant responses before lowering or raising input EC levels. If you notice deficiencies and/or light green growth increase feed strength, if you notice tip burn and/or darker than normal green leaves decrease EC and/or push for more runoff.