Getting close spark. Even with the ultrasonics ya need to install a damper or baffle system. Still need to do debounce on really rough days, that's why being programmable is a nice feature.
Typical ultrasonic set-up:
Measuring inside of a tube will be much more accurate because the water level inside the tube will be more about pressure level than water surface fluctuations. The deeper the PVC tube is, the better, so put it close to the bottom without filling it with debris.
You could use other types of switches in a rig like this, but there are other way's to isolate what's happening on the pond surface to get accurate level indications for control. This is just plain simple and works! Most will be similar tho, but the tube works best.
I figured I would post this for esshup to keep him awake at night
Back to the OP:
You mentioned a variable speed pump. What is this animal? Manufacturer and model number of the control would help. The pump itself is a dumb gizmo and needs to be told what to do, therefore, that's what the control does.
If you get me the information, and the engineering manuals are online, I'll read them and tell you what you have. You could have something smart enough to do the pond gig or a dumb black box for pressure control. Don't know, but if your well guy installed it, quite possibly a dumb black box for residential service.
