Herbie or beananimal

[Skimmin]

I use one extra hole as a second emergency even though its somewhat overkill I know two 1-1/2" drains could never plug enough to have a problem. My one inch throttled drain feeds only the fuge side of my sump and my heavily throttled inch and a half drain feeds only the skimmer/mechanical filtration side of my sump. I also have the choice to change configuration for whatever reason down the road or if I wanted to I could increase sump flow or experiment etc... Seeings I had the overflow custom built I figured an extra hole could never be a bad thing. The real key is finding the best height of the pipes in the overflow to keep it dead silent.
Also I don't run a trickle. Just spent a fair bit of time and got it perfectly 'tuned'. I can shut the tank down and start up and within about 5 min its perfectly quiet.

[Ron99]

I went BA when having my tank built because I figured the extra emergency drain is an added safety feature just in case. So why not?

[Duckhams]

I run a beananimal on my 75 gallon with 1" drains and it handles my eheim 1262 (900 gph) easily. I would suggest using a gate valve, not a cheap ball valve, on your main line for easier adjustments and fine tuning.

[Doug]

My BA. Three in. drains. You guys inspired me to drill another hole and have it quiet rather than the pair of duraso

[Duckhams]

That looks good Doug! I'd add a small length of tubing to the secondary line on the left and bend it over slightly to redirect any spluttering that might be caused by the siphon restarting after tank cleaning etc. Probably not needed, but if you wanted to be fussy.