I'm fairly new too. Slayer is almost identical to the Revo which is my first car.
Battery will be underneath the receiver and servo wiring. Remove the lid and look. Charge point will be underneath car. I assume its same as Revo and will have a charge port.
You should not be having to clean filter after every tank.
Make sure the truck battery is charged fully and your radio batteries are good.
After the 1/2 tank death, will it start back up?