Me again, I noticed that it is not possible to transfer fluid from ic2 pumps or tanks and investigated a bit. Placing a fluid reader on an ic2 tank gave me the output of isTank false. I'm pretty sure that it is, indeed a tank I'm using, so it should work. Not sure where the problem is, most likely ic2 api but if it is possible, could you fix it?

EDIT: doesn't only concern the ic2 pump and tank, it's all ic2 machines using fluids
Daenara

slightly off topic PS: which mod are the tanks used in the screenshots from?

I just came across your IC2 forum post, so I guess you have your answer there.
I used to support the old fluid handlers back in 1.9, but removed them when porting to 1.10 to avoid having to maintain two separate systems.
If I understood correctly, the IC2 devs will implement the fluid capabilities soon, so this issue should resolve itself then as well.

The tanks are from EvilCraft by the way, a tech/magic mod I developed.