I don't run ovone through mine, so I can't help you there, but I hadn't heard of running activated carbon on the outlet. I would think that would slowly cause a change in backpressure as the carbon gets plugged (not mention the initial additional backpressure from having to go through the carbon). If you were to do it, running off the gate valve mod may be the way to go. I just hooked the gate valve up to mine (G5) and it is 90% (swag) quieter than it was with water cascading.