Reversible Jabsco Pumps

I'm adding another bag and pump for the front. Quick question...when using a reversible pump, does water fill and drain from the same thru hull? I'm sure this is a stupid question, so forgive me. When using with a ProX sac, I only should have the hose going into one connection right? And use one connection for a vent line? You only use all three connections on the sac if you have separate pumps for filling and emptying, correct?

All sounds right Taft. You could rig a separate drain with a T and a one-way check valve if you wanted to drain out of a separate thru-hull above the water-line.
Lot of people put a one-way check valve on the vent line.

Yup, same thru hull, at least that's how we run ours.

Thanks for the clarification. What happens if you don't use a vent line? Lastly...what model number and who has the best price on these?

http://www.discountmarinesupplies.com/Washdown_Sump_Utility_Pumps-ITT_JABSCO_WATER_PUPPY_WATER_PUMP.html 150$ here

Greg - the one in the link is not reversible. I found this one...has the rocker switch included...but was hoping to find it cheaper.

http://www.wakeside.com/product/boat/ballast/ballast_pumps/jabsco+wakeboard+ballast+puppy+reversible+pump.do

The pump on Greg's link is reversible it should be the exact same Water Puppy that wakeside sells . . . I know it says not reversible but I'm pretty sure it is

my fault man didn't even catch that

http://www.pyacht.net/cgi-local/SoftCart.exe/online-store/scstore/h-jabsco_water_puppy.htm?E+scstore try this one and i thought all water puppys were rev call and find out