Mitty vac break bleeder

[$Evan$]

so i bought one used it once and i am not sure if i like it. its easy to use but i burn and churn through canister of brake fluid. my question is when you pump it from the handgun and it goes into the little resovoir cup can i use what was bleed out from the cup as long as is its new brake fluid? it seems like such a waste not too. will i be contaminatin the fluid if i do this?