New tactics?

I'm worried my hubby doesn't make much sperm as hardly anything seems to come out. Now going into month 9 ttc and getting more gutted as time goes by. Is there anything I can do to increase the amount he makes as I'm worried that's the problem. And we BD every day in my fertile week. Is it best to try every other? Think that will be hard though as I want to do it every day to make sure as much as possible has gone up there!