We use a flojet as well and have no problem with 6-7' of rise. As per the manufacturers instruction, the pump is not to be used for long durations continuously. We have not carried a slinky hose in 4 years... strictly use the flojet. Pump it out, give it a good rinse with the tank flush, pump it agian.. good to go.
2014 Rockwood Ultralight 8312SS Diamond Edition
2016 F350 Super Duty Crew Cab Lariat Ultimate 4X4 6.2L