For a light weight pump look no further than this 25D 12V Rule Pump. This pump is compact and made for smaller vessels. To turn this manual pump automatic you will need a Rule Float Switch. Featuring a quick release inlet strainer to make cleaning a breeze as well as using low amp to consercive the batteries. Ignition protected and a tough plastic body completes this pump.
Specifications:
Designed to be used with a 19mm (3/4") hose
Output: Up to 6 gallons a minute
Uses a 2.5 Amp fuse