How can a small magnet can turn a small propeller …?

How can a small magnet can turn a small propeller without the use of small batteries or electricity? I mean, do this, on the same concept used in the mini fan found in China this page: http://hotproducts.alibaba.com/manufacturers-exporters/Mini_Fan.html and that this (the small magnet and small propeller) while under the water all time. Please help me … I do this for a new aquarium. U If you need more information please ask me and I send to my e-mail U. I want to do the same effect This mini fan, but under the water I need to know where in the U.S. this type are similar to mini fan … well you need to know how to really work on details, please

I think you're wrong, I could not find the fan who is talking, that does not require a battery. Obtaining rotation only a magnet in itself is a bit of the holy grail of enthuists "free energy"! (It can also be regarded as a perpetual motion machine). Personally, I think it's possible to get that, but gauss magnets (de-magnetizing) so its not really free energy …

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