Fuel transfer speed of interstages

I used this craft.
~254 kg/s . That’s it. Every interstage can transfer that amount of Kerolox every second.
For Hydrolox it is ~79 kg/s.
For Methalox it is ~179 kg/s.
For liquid hydrogen it is ~17 kg/s.
For water it is ~249 kg/s.
For xenon it is ~449 kg/s.
Jet-fuel didn’t work like the other fuel types above did. Instead I had to transfer it manually. The rate of that was ~199kg/s. I tried this method with some other fuel types and got the same results as with the interstage.