What kind of anti-freeze to use in 2000 LXI Aqua-Hot?

[luckyron1]

I note that the tank is a little low on the aqua, blue/green colored fluid so I
called Aqua-Hot for this and even with an Aqua-Hot serial number the man
couldn't give me a definitive answer. In 1999/2000, he said, Aqua-Hot
used/recommended Etheylene Glycol (green) in their manufactured units. However,
the man said that he knew that BB used Prophylene Glycol (could be just about
any color) instead. I'd hate to wind up with a bad mixture. Anyone?? Thanks.

Ron & Ruth
2000 LXI in MN