siphon break

I’m setting up my new tank with a fish room on the same level but separated by a wall. The best solution I could come up with for ATO was to run RO tubing up the wall, above the ceiling, down the tank wall, and into the sump. The Neptune ATK pump seemed powerful enough and it is! My problem is...

I already have a small hole drilled to my return nozzle in order to break the siphon when my pump is off. The problem is that the hole is to low from the water line causing more water then I want to drain into my sump. The question I have is if I make another small hole will there be any issues...