how many kw's do I need for a heater element.

[bbqbrisket]

My Spa/Hot Tub/bucket of water  sits outside and holds about 80 gallons of water.  It's a 6x4 so relatively small.
It uses one of those approx. 2 x 10 inch inline heaters attached to a Balboa spa pack.
I see that most of the replacement heaters are either 4.0 kw  or 5.5 kw
I'm running the spa on 220v.
What size heater should I purchase.
thanks in advance for any help or advise provided.

[Tman122]

My Spa/Hot Tub/bucket of water  sits outside and holds about 80 gallons of water.  It's a 6x4 so relatively small.
It uses one of those approx. 2 x 10 inch inline heaters attached to a Balboa spa pack.
I see that most of the replacement heaters are either 4.0 kw  or 5.5 kw
I'm running the spa on 220v.
What size heater should I purchase.
thanks in advance for any help or advise provided.

First off 80 gallons? Is it 8" deep? (didn't do the math) If you have the amperage required a 5.5 will take less time to heat and will recover heat quicker that a 4 KW