A couple bait tank battery questions

[GregAndrew]

I would mount the battery box right to the tank if possible, with the switch on the box. Much more compact and transportable that way. You might want to consider a 500 gph pump if you are going to use a 6v and plan on carrying much bait. Sardines don't fare so well when the O2 levels fall a little or the water heats up much.