Wha? I thought I was going to read about getting into a motorized tank and firing a stream of lava at my enemies! Noooooo!!!!
Lots of uses for tanks in your ship, not just liquid. maybe even breeding/cloning tanks, for that awesome creature you found that you want to be in every planet.
Actually maybe something like that will be in the game they said something about getting your own homeplanet and you would be able to terraform it. Taken from the wiki this might be true and vacuuming water up might be a part of this terraforming as they said you could terraform nearly every aspect on the planet.
Maybe you could even release some of the stored fuel into tanks that you could place in your inventory and use to power other things.
