saucerman

Spa: caldera martinique paradise - 2014 using saltron mini spa sanitation system since 2014, replaced in 2020 2016 heater was replaced under warranty Both jets replaced in 2020 regular maintenance was drain every 3 to 4 months, clean, replace filters when needed, up until I was away, it seemed to stop running during this time as I notice the breaker was thrown and if I switch it back, within 10 seconds it's blown again - I suspect the heater this time again... pictures included....heat pipe looks to have some corrosion goop on int

So we were away for awhile came back to an out of order hot tub (hopefully I can fix that), but when I opened the lid, I never seen anything like this, the horror....from all my jets, it's this black paint like stain, and it's really difficult to get off with just scrub bing....any clue to what this stuff is and how to get rid of it would be greatly appreciated.