My bilge pump sucks...
I had an extra 12 V washdown pump so I just hooked it up to a small switch put the pick up down in the bottom of the bilge hooked to a little brass screen. Sucks it pretty dry.
The only way to have a totally dry bilge is just to stop all the leaks. 💦But you'll be chasing that forever.
Water gets in who knows where or how, it just gets in.
If you can't repair it maybe it shouldn't be on the boat