I'd like to set up a herbie overflow on my 200g reef ready but not sure how it will work. I have two overflow boxes on the tank, each has one 1" drain and one 3/4" return. If I set up the two drains as herbie, that leaves one 3/4" for return and one 3/4" for emergency- but that is only in one of the overflows.... if the herbie on the side with the return gets clogged, the entire overflow will fill up.... I've read and read as much as I can on herbie's but I don't see anything with two overflow boxes, other than prskiller's. Will I have to settle with either running an external return, or doing a durso or similar on the return side?