Josh

Strange that the water pump drains your battery instantly like that. The
fuse is 3 amps, meaning it only takes probably 1 or 2 amps to run the
thing. When you crank your car, a good battery will go down to about
10.8 volts, and I assure you the starter pulls a lot more energy than
the scrawny water pump. I would look at the alternator/voltage regulator
to insure a healthy electrical system first.That's was my $0.02 worth.

Let us know how you like the gel cell battery.

Alain