Bucket Heater users

Mine should be here this week, i was just wondering what you guys use as a formula for your heating? The only mention that i saw was 23 degrees per gallon per hour I think. Is that accurate or is there something else that I should start with.

When I get it I may just through it in a gallon of water for an hour and see what happens.

I guess it depends on the heater - the one I use is 250F per gallon per hour. So it raises five gallons 50F per hour.