"The game crashed whilst initializing game
Error: java.lang.NullPointerException: Registry Object not present: mekanism:basic_fluid_tank
!It worked at first!,but then after putting in some more mods into the folder,this happened.Deleted ALL the mods,refreshed forge(let it run without any mods and closing again),put in only Mekanism again,worked again until i put storage_overhaul again(true,its for 1.15.2 but that shouldnt induce a problem with mekanism itself), so i deleted it again,didnt work, did the steps listed above again and now i cant get it to work again even with only Mekanism installed.
Mekanism and Forge up-to-date.
Minecraft Version: 1.16.1
Update: Apparently i had a hidden .jar file of ironchests still on it. After deletion the game started up without crashing. after starting the game up with ironchests again,the problem occured again. Problem solved.