DIY Pvc Overflow Questions

[JESTERX626]

Does the two bottom U's, outside the tank and inside the tank have to be near the bottom of the tank? I followed this guide and cut everything to precise size but it says 55gallon:
http://www.monsterfishkeepers.com/forums/showthread.php?t=219465

I'm making this for a 135gallon that is 24" tall.

So do I need to change my design up? Like longer pipes here n there, etc.

 

[chemicall]

If you cut it all as the guide says, it will function fine. the U-bends don't need to go all the way to the bottom of your 24" tank, 13.5" pipe to the U-bends is enough. Just remember the inner and outer lower U-bends should be at the same height, and to keep your vent above water level.