Herbie or beananimal

[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.