We keep a kiddie pool for our geese, but I am thinking of buying my neighbors used 2'Dx12'DIA stock tank for them. It's deeper so they can actually paddle around in it and obviously has a much larger surface. I am looking for an economical vac system for cleaning the muck out of the bottom in the morning. Emptying and filling a huge stock tank just isn't economical so I am looking for something that will vac the muck out, while losing as little water as possible. Does anyone have experience with the so-called "Venturi-Effect" pool/pond vacs? Instead of using a huge vac system, they just use water pressure from a hose to create the vacuum, and either a bag to catch the wast or a hose that will eject it out onto the grass or into a bucket. The ones I have seen run anywhere from $70-100, while the elaborate vac systems run upward of $400. I love my geese and want them to have the best pool possible, but right now a $400 vac system is out of the question, so what I would like to know is this: Has anyone used the hose-powered vac wands and have they been successful in pulling the muck out of the bottom of the pool? I did speak with a rep from one company that makes them and he told me it would take forever to vac the muck up, and then promptly tried to sell me his $400 model, so I suspect he was trying to bs me. The models I am interested in are the Muck-Vac, and the Python Pond multi-vac, but if there are others out there, I would appreciate the information. Thanks!