80A is probably too small. I had a 150A fuse but it burnt several times when I tried to get on the board in choppy water (peak current was around 70-90A but this was enough to heat up the fuse and it finally burnt through). I‘m going to change it to 200A.
https://www.reichelt.com/ch/de/car-fuse-midioto-200-a-58-v-purple-imaxx-mdp200-p290809.html
Fuse holder:
https://www.reichelt.com/ch/de/fuse-holder-midioto-imaxx-hmd1-p229126.html
It is quite compact, there are other fuses but they are larger in size. Max available Midito is 200A. Try to find at least one for 48V better higher.