Which one has the pipe?

So the variations are very interesting indeed. I would think the one most likely to stay open will be the one which reaches the surface with the greatest associated water velocity. There is a de-icer that is a available that is built on this principle of moving water to maintain open ice.

I think the pipe idea is a good idea because I think it make the water moved more efficient and it concentrates the energy over a smaller area. A bigger pipe over the quad might even be better. Anyways so far so good!

Common sense is not so common - Voltaire

It isn't what we don't know that gives us trouble, it's what we know that ain't so - Will Rogers