I have 5 watertight areas so I have 5 bilge pumps with discharge loops. Each area has an additional high water alarm 1 foot higher. I also have a portable bilge pump and a place to plug it in which I can move to any area. My biggest problem has been air lock in the pump. The water builds up and the pump runs but no water is pumped. This is partly caused by a check valve in the line which I use to prevent pump cycling (until the batteries die) (yes I agree they can not be used in lieu of a discharge loop). To remedy the air lock I drilled a very small hole (1/8") in the output flange not covered by the hose. I'm happy with this set up. Edmond Badham COSMO Cape Fear, NC Wilmington city council is so corrupt I have changed my hailing port. Looking to relocate... any suggestions?