I have 2 offshore boats. A 30 dorado with a single diesel and outdrive. The other is a 34 center console with twin 300 evinrude. The diesel will burn about 85 gallons there and back while the other will burn every drop of 210.

I have to really keep an eye on the burn rate. Often. I will troll for a few hours or more

I have been out there in a 23 pro line so your 29 should be fine.

Not sure when I will go out again but will let you know