Sorry if I wasn’t clear. In what I described, there are 3 total drains. This is one more than herbie. There is only one coming from the pump. As you stated, you have enough in-tank flow in the tank with the the MPs. Just because they are in different towers doesn’t mean that the whole tank isn’t covered. It is all based on the level of the water in the tank.I just absolutely hate the sound of overflow drains, and I’ve already spent a lot of money on quiet equipment like dc return pumps and skimmer etc. I also just want the extra safety of the emergency overflows on the Herbie style.
I can tell you that my tank was dead-silent with this design.