I'm going to buy a minkota maxxum 24 volt variable speed. Right now I use to batteries wired parallel so that I can use a 12 volt motor all day long. I also run my electronics off these batteries. When I switch to this new motor will I still be able to run light, aerator, bilge pump, and fish finder x2 off these, OR will they all have to go on my starting battery. I run a 30 hp engine, so I don't need alot to crank it. My definition of all day is daylight to dark or dark to daylight, so when I say all day I don't mean 6-7 hours, I mean more like 12-15 in summer.

I have a 24V motor and use my starting battery for everything. It is possible to use your deep cycle batteries if you wanted to though.

Keep a cheap set of jumper cables in the boat. If your starter battery gets low, you can jump it off of one of the trolling motor batts. and get back to the ramp.