I just received the Modular Marine external overflow 800gph.(rated for 150gal tank) for my upcoming 90 gallon mixed reef build. I was diappointed to see it came with 1/2" uniseal bulkheads. Totally my fault, it's clearly in the description. I want to run 1" pipe as drains. Will a reducer work or will it create a back flow? MM does do 3/4" upon request so I wondering if I need to do an exchange. Thanks in advance for your input!

