Here is a chart to show what cooker will fit your needs and speeds.
Chart NOTES:
Minutes to BOIL is the amount of time it takes for the cold water put into put at start of fill.
Minutes to RE-BOIL is the amount of time it takes for the water to come back to a full raging boil after putting in the crawfish(or whatever food) into the newly boiling water. As it always stops boiling immediately after dropping in food.
Crawfish are purchased live by the sack, and a typical sized sack usually contains approximately 32 pounds of crawfish.