The absolute bare minimum for how many grains of total arrow weight per pound of bow weight is 8 grains. Always check with bow builder to be sure. So you're shooting 45# which would give you a minimum arrow weight of 360gr. I personally like to keep my arrows at 9.6-9.8 grains per pound of bow weight. For the way I shoot and how I like my bows to perform and feel when shot, this is pretty much my rule of thumb.
Just remember when it comes to trad bows, broadhead sharpness and arrow weight does the killing. Kinetic energy and a well placed shot takes care of the rest.
My opinion only. Hope it helps.
By the way I shoot Montec 125 gr heads on a Carbon Express Heritage 250 arrow.
You will find folks on here with a vast knowledge of about any trad question you can think to ask. You won't find a better group anywhere period.
Best of luck