Here is what I use on my three acre and one acre ponds. Internal battery good for about40 gallons before it runs down:

http://www.northerntool.com/shop/tools/product_200332331_200332331

I generally don't use it as a backpack, just take it out in the boat or carry it around the bank.

"I love living. I have some problems with my life, but living is the best thing they've come up with so far." � Neil Simon,