I have built a few bell-siphons now, re-built some and adjusted all based one the grow bed and intake flows. Although all are based on the same basic design, none are exactly the same. All are monitored by my Arduino system allowing cycle time calculations. The grow beds inflow rates are also tracked. The grow bed intakes are off a common feeder line and drain into a common take away line to the sump tank.
They use a simple, and really cheap
EC type siphoning state detector: open circuit is not spinning and shorted out for siphoning. A couple of stainless steel bolts and some wire is all required.
I just added a “dutch bucket” extension using six 5gal. pails in a parallel configuration with a single side feed/drain line near the bottom. The buckets are also in an ebb and flow configuration with a single in-feed at one end of the common feed/drain line and an external bell siphon at the other.
This has turned out to be the best, easiest to build/adjust and most stable bell siphon that I’ve ever built. Here’s a picture of the setup:
Connect the two wires up to an Arduino and sample the analog-in.
I sample at one second intervals using 3 like samples out of the last 5 to determine the current siphon’s state - it just ain’t rocket science, you know. Simple and accurate enough for determining state and cycle times.
Backyard Aquaponics
