Need help with high output fog machine - can't find a consistent answer

I have 0 experience with fog machines and have spent many hrs on the internet and calling companies and nobody seems to provide a consistent receomendation so hopefully someone with actual hands on experience can help even though not for halloween.

Situation - Purchased a 20 foot inflatable tunnel for a high school football team to gather in and then run thru -all in about a 2-3 min span..It came with a Chauvet 1301.. used it last week and although good output, it only shot out fog for about 8 seconds then no more fog for about 45 seconds which did not get me much fog overall and they refunded my money..

From speaking to many companies I am even more confused. Several said the Chauvet 1800 flex would work because its 1800 watts and the higher the watts, the longer the output and shorter reheat time and it had the flex feature to control the angle. Others say American DJ 3000 or 1700 HD. because they advertise no reheat time but I have to believe they do.. Still others the Antari Z1200.

Other points -due to logistics 2 foggers are not an option. Budget is around $400 max as I am dealing with a school and thats all the money left for the fogger and juice.

What fogger will give me the longest output with the shortest reheat time in the 2-3 minute span I need. Will only be used 5 times a year for the 5 home games. I realize I am not going to get the effect of NFL teams running thru smoke as they are on high budget foggers I woudl think, but still want to get whats best for my money....

I have to order this by Monday Sept 22 to have it for next home game so any recomendations from actual users woudl be greatly appreciated.