Siphon pumps are for the weak. In fact, you suck at aquarium keeping unless you use a legnth of flexible plastic tubing you bought at home depot as a siphon. It's easy not to get tank water in your mouth; just stop sucking a few inches short of your mouth. Besides, if the water parameters in your tank are good, then your water shouldn't be particularly bad-tasting. Tank water is not particularly good for you; the KNO3 in your water is bad for your heart. On the other hand, the amount of tank water I'm likely to ingest over the course of my life will have an insignificant health impact.