Resolution: Works As Intended
I discoverd that a Sea pickle onder water is a hot light source and it let melt only Ice (no snow)
I would expect a plant to be cold.
Edit: 1 to 2 sea pickle's does not melt ice. only 3 and 4 pickle's
Fact "sea pickles like to hang out around 130 feet (40 meters) below the surface, where the temperature is cool"
Also a sea lantern is a hot light source. and let melt ice AND snow what is supposed to a cold light source.