I have an Aeroflo2 30. I've only used it for one grow so far, with GH Flora 3 part nutes. I was burning my plants up with an EC of just .70! When I grew in GH Waterfarm Hydro units, my EC was almost double with no adverse effects. So, speaking from my own experience, for the Aeroflo2 I keep my nutrient solution at an EC of no more than .60 (300-420 ppm depending on the type of meter you're using). This is very low from what I've read others are running their nutes at, but I gotta listen to what my plants say. I'd love to hear from other Aeroflo2 growers and see what they say. Also, the pH in the Aeroflo2 drops as the plants grow. Anyone know why? I wish I did. In all the other hydroponic systems I've used in the past the pH rose, not dropped. I change my nutes every 10 days. Can't comment on yield yet, due to some hermaphrodites which pollinated my buds and destroyed my crop, but I'll have a yield report for you very soon, so stay tuned... Same Bat Time, Same Bat Channel