You know them insulated plastic tanks with wheels on the bottom that you see in gas stations that are full of ice and drinks. I have one of those for a vat. It's a bit of a hassle but after each trip when I get home I put my minnows in that. I have water, an aereator and baitsaver in it. I drain the water off my minnows before I put them in there. If I go the next day I just go get however many I want. If it's 5 days before I go, I still have minnows. I have had up to 3lbs in it for several weeks. I too use an Engel bait cooler and keep the aereator going on high and have a frozen water bottle I put in there to keep it cool. The warm temps will kill minnows quick! I had 12 dozen in my 19qt (4.75 gal) Engel and my buddy had 8 dozen in his uninsulated 5 gal bait bucket. 75% of his minnows died by the end of the day, I lost 6 minnows all day. They are expensive but they do their job. If u do start using a vat at home be sure to change out about 1/3 of your water every day or 2 and store them in the shade.