Thanks for showing me that. At first glance, it looks like there is a very fine line between the correct flow over the weir and the pump running dry. What kind of water level needs to be maintained for BA to work? I ran my Herbie with the level about half way up in the teeth.
the water height at the weir teeth is purely dependant on the lph the return pump is set to and how much of the water flow is restricted by the teeth.
The beananimal setup is tuned to suit the speed of the return pump essentially. Not sure what you mean by saying the pump will be close to running dry. This will only happen if you don't top off the evaporated water.
The only water level that matters really is the level inside the box with the 3 drains be that an internal box or external.
This water level is essentially determined by the height of the Open Channel drain. and really that only matters if you want a silent system.
From memory I think you want the heights to be something like this....
Full Siphon - Any height, I have the inlet of the 90 degree bend about half an inch-1 inch from the bottom of the box.
Emergency drain - 1 inch from the top of the overflow box
Open channel - The hole drilled in the top of the two 90 bends should be about 1/4 of an inch from the height of the emergency drain.
With the above when you turn on the return the box fills up.
The water level goes above the open channel air hole causing it to create a siphon.
The water will continue to rise and then drain down the emergency pipe.
Meanwhile the air in the full siphon is being purged and inside the open channel.
The water level drops and eventually means air can enter the open channel.
You then tweak the
gatevalve on the full siphon so the open channel only drains a small amount of water and is silent.
Ideally you don't want the water level in the box too low otherwise the water will have quite a drop over the weir potentially causing noise but ive found the level has to be really low to hear the water.
