Water Siphon

I've searched all over this site and can't find what I'm looking for...so with that said, I need to install, set-up, an "auto-siphon". In the process of a straw bale build, end result completely sustainable, no utilities. My thoughts for water... I am planning on having a 200 gal tank in the loft for providing gravity fed water. This will sit right over the shower, so no problem with pressure/flow there. However, the kitchen sink will be 25 feet away in a level line until I have the 4" drop for the faucet. In my opinion, not enough head.

To remedy, I would like to set up what I've termed an auto siphon. I'd like to run the water line up to the ridgepole, overtop, then down to the sink. Doing this I can create approx 25" of head. I believe if I install anti-siphon faucets, I can keep the siphon activated by turning on/off faucet. Only time I can visualize problems is getting it started or if my tank runs dry... At this point, I've searched seemingly endless hours on the 'net, with no results. At some point, I will need to address this with my inspector (who has been very unhelpful, to say the least), so I need good detail, and great ideas!

Any help would be appreciated!

Thanks!

The total head only depends on the height of the source tank, and the relative height of the outlet. What the water pipe does in between has no effect on head.

If that were not so, you could get water to flow from a lower tank to a higher tank just by running the pipe higher in the middle.