what would cause brake fluid to need to be filled often,brakes work great on 1990 Ford Tempo

i am filling brake fluid about every 3 days

Asked by for the 1990 Ford Tempo
Brake fluid leaking. Check brake lines, wheel cyclinders, or between master cylinder and vacuum booster. The easiest way to check is in the morning look for a wet spot on the ground. You can also press the brake pedal a few times then look under vehicle for dripping fluid. The fluid is going somwhere you just have to find out what is leaking.