Progress, and a Failed Experiment

Today I was able to procure many additional materials: plywood, polystyrene panels, 2x4s and 4x4s, plus some plumbing supplies for further experiments.  I assembled the three grow-bed support frames.  I had to obtain a larger container to carry out the siphon experiments.

As I had mentioned in my last post, I had a crazy idea:

A miserable failure - do not repeat it!!

Yes, this is a two-stage inside the same bell.  IT DOES NOT WORK.  This is why I take notes on these things...it's just too bad I didn't actually re-read them before attempting this hair-brained idea.

Why does it fail?  The small red pipe feeds directly into the large main pipe.  There is no way enough water can flow into that massive blue down-pipe to form a siphon, therefore the siphon simply never forms.  What made the original 2-stage experiment successful was that the starter siphon formed a full and fast siphon. With the additional water being pumped into the larger out-piping, there was sufficient volume to start the larger siphon.

That is not the case with the above illustration.  What you see above is simply a slow flow into a very large pipe, which would happen even without that extra red pipe sticking out the side.  Without an actual siphon forming with the smaller pipe, there is insufficient water flow to trigger the main siphon.

Some other bad points about the above design: it's huge, it requires a very large diameter bell (which equates to an even larger media guard - bleh), it doesn't work (as previously mentioned), it requires many more fittings than its worth, and so on.  I will be trying some more experiments soon.  Namely, I want to see if a 3/4" starter siphon will trigger a 2" main siphon.  If it does, my next experiment will test two 2" main siphons with the 3/4 starter.  I can also modify the diameter of the out-piping, to help ensure the flow is sufficient to trip the other siphons.  The catch is that the smaller the out-pipe, the less flow it can handle, so there may cease to be a reason to run 2" siphons.