Amplifier Wiring

If I am going to wire a Hifonics Brutus that has 3X40 amp fuses, should i put a 100 amp ANL fuse, or a 150 amp ANL fuse?

150 or 120 if you can get one

i was wondering this because wouldnt it be better for the fuse to be smaller so that if the amp pulled too much power it would shut off lower than the amps fuses rather than higher and take the chance of frying. also am i thinking about this the right way?