Still got a full resevoir-- but when that drains it takes a full ton of fuel I think.
You should try exploring.
The number of times I end up in a brown dwarf field with like 3 tons of fuel is scary as hell-- I mean I've had to pretty much rely on luck that there are scoopable stars within jump range at these times.
Thankfully I've run with that luck for now and it's held out, although I impacting a brown dwarf twice might be the game's way of telling me to plan my routes better.
My second (or third? I can't remember) exploration expedition was a resounding success.
When I got back I made like 4mil from the data-- just imagining getting back only to get stuck in a field of brown dwarfs with no fuel is scary as hell.
If I ever do a Sag A* run you know I'm gonna run with extra fuel tanks. My Diamondback already runs with an extra 16t fuel for these relatively short runs of 2500-3000Ly.