Cabinet screws all the way. Besides the washer head the threads are different than a regular screw. Do some googling to find what you need for what you are doing.
Sounds like the tank is not venting. Try running with the cap off. Im assuming it is a portable tank and you have already ensured the vent screw on the cap, if it has one, is open.
I know this setup is way diff than mine but I could not identify leak location(s) by filling up the boat. The sand silt and muck plugged the holes. Until I ripped the floor up and cleaned out no water dripped. Do it anyway just thought id chime in on my experience.
Time for rogers to choke, soon but dont think against the Bengals
Fun to watch vrable back in tn to win
Chargers for home field advantage
May the correct teams win!!