I have 2 dogs (akita 2 1/2 and Great dane 1 1/2) both are fixed but both keep fighting. Need help...?

I have tried everything in getting my dogs to quit fighting. NOTHING works! Someone told me to try pepper spray just as a back up but im hoping there might be something else i can use. Water wont work and I have done the Alpha bit with both dogs. Sat on them, held them down, etc. I have watch the dog whisper and nothing. My Great Dane is a passive dog. He would rather watch the grass grow than fight but when my Akita growls he goes on the defensive (protective) but my Akita is a different story. Nothing you do with him changes the out come of a dominance game. I'm at my last thread. My husband even went and lifted both Dane and Akita at the same time by the necks and the Dane went still, tail between the legs and licked my husbands hand while bleeding, but my Akita waited until my husband lowered him back to the ground and he went at it again. My Dane cant take this much longer.