I use a standard remote line - but I attached it to a scuba fill station.
so I use this:
but I take the part off that you would normally connect to the tank fill nipple - and I install a remote coil first - then use the remote quick disconnect into the fill nipple on an air tank. That way I'm dumping the air at 3k psi into the paintball tank and using that tank's reg to output to my gun.