I know that the topic of batteries has been heavily discussed but I have to add to it with another. Today was my first outing with my new Garmin Striker Plus 9SV. (love this upgrade for me). Also my first issues with it. Here's the stage setting. This is in my 12 ft pond and small lake jon boat. I use 1 Group 24 deep cycle battery to run the Garmin and the 40# tm. Today after about 1-2 hrs of use the Garmin started shutting off. Then I noticed that when the tm kicked on the Garmin shut off. Then while checking for a loose connection I found that the pos post and connections were hot. Soon the tm stopped due to low battery. I figure I may have some options to remedy this.
1) add a second battery for the Garmin only but space is limited.
2) get a larger battery such as a group 27 deep cycle but not sure it would help.
3) try replacing my 3 yr old deep cycle to see if it helps.

Any tried and true cures for this situation?