first of all let it be known

i am not an expert

hoo ever, you are pushing fuel to two engines as i see it,im guessing one is a spare:question:therefor wasting what you have sent to the spare engine:exclam:
personally i wouldnt run with one tank either,two smaller ones would be my choice
also

dont be offended

i take it you carry spare fuel and a funnel,for transferring