I already have a trolling motor and I'm thinking of getting a fish finder. If (okay, when) I get the fish finder, is it okay to run them both off of the same marine battery? How badly will that affect the life of the battery and will it affect either of the electronics? Right now, I have a 55lb thrust minn kota that uses pulse technology to extend the battery life (and quite well). Basically, I'm considering either a fish finder that attaches to the marine battery or one that runs off of a bunch of AAs or similar. Thanks for any advice.

--Bank Angler