Hey Elijah,
Thanks for your purchase with 420 Science! We appreciate you taking the time to review this product! The flame should last up to 60 minutes! A good indication that your torch is full is definitely when it starts spraying out like that! It doesn't take much to refill it! It's pretty quick! :)
Here is an instructional video on how to refill: https://www.youtube.com/watch?v=m3o5EO7VZXw
Hope this information helps! Reach back out if you have any other questions or concerns!
Best,