I havn't tried your idea nor do I know any who have. It is a good idea. However I feel the need to inform you that a lot of what you pay for from the big companies is the pump. All the tubing and connectors are cheap from local plumbing suppliers the mist heads and the pump is where the money is. Those just happen to be the important factors as well. To me I would much rather pay for reliability.
By know means am I saying you should buy from the big boys but know what they offer. I would look at what compaines like Ecologic at cloudtops.com. Patrick from Saurian get his stuff straight from ecologic cut out the middle man and see what they have to offer.
I don't think you will be disappointed. But if you still choose to build your own good luck and let us know how it turns out.
Jeremy
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"I am become death, the destroyer of worlds" July 16, 1945 Robert Oppenheimer
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