You are side tracked chasing that tiny bit of algae behind the light. There is no way that can account for the FC loss you report.
I have no idea how your FC consumption could have been at that level but I suggest you go forward and forget about the past.
Finish the SLAM now (do an OCLT each night). You should be VERY close to completion.
I have no idea how your FC consumption could have been at that level but I suggest you go forward and forget about the past.
Finish the SLAM now (do an OCLT each night). You should be VERY close to completion.