I dont know anything about sumps!

[SeaHorse_Fanatic]

Or you could crank up your stereo really loud so you can't hear the sump

JJ

Any holes you don't use, you can just silicone a piece of glass over it because if you ended up using all 3 holes, that some serious water movement which would require a bigger pump & create a lot more noise.

JMO,

Anthony