Quote Originally Posted by foodchain
If one bell doesn't drain off enough water to keep up with the big pump...do I add another bell and put each bed on it's own bell, or enlarge the one and put a splitter or Y at the end branching off to multiple beds?

How do I determine the maximum range I can move in the IBC? Ideally would like to move a max of about 2 ft of water at one time...but the needs may change...so I figure this would need to be adjustable.

Seems to me, 4-5 small bells would be better than one big one.
You need to balance the size of your siphon or siphons to the input rate. Too small a siphon won't keep up with fill rate, and if it does, it may not break siphon properly at the end. Likewise, too big a siphon for the fill rate may never get siphon going properly. Multiple siphons could be a problem because unless your standpipes are totally EXACT in length, one will start before the others and the remaining ones may never get fully primed to flow. You might be better off doing the "Y" thing with a single siphon. Be sure to allow for adequate space for sufficient downflow below the siphon exit to keep the flow going. How far above ground level is the bottom of your IBC?

I suggest experimenting with a bell siphon in a 5 gallon plastic bucket so you can understand the concept better before trying it out on your IBC. PCV is cheap and easy to experiment with.