I hope this question doesn't seem too dumb, but we're still going through the newbie phase. We have an Eshopps ADV-200 sump/refugium that just arrived today. Our tank has one internal Megaflow overflow. It is off center in the back of the tank with 2 holes drilled in the bottom of the tank, one 1" hole for the drain, one 3/4" hole for the return. The new sump has two Drain holes. Should we just not put anything in one of the holes, or use a 1" PVC Y fitting to run the one Drain line to both holes? Also, we have a Quiet One 4000 pump, which has a 1" MPT fitting for the outflow. Can I put a regular 1" threaded to 3/4" slip PVC fitting on this to plumb from the pump to the tank? Thanks in advance for any advice.