I have had moderate blood in my urine for 25 years..at first, went thru all the necessary testing and all were negative and i have been fine ever since. is it possible that some people simply have blood in their urine for no reason. (25 yrs?

Yes, it's possible. But if the quantity/quality/amount/ volume change with or without symptoms, it should be checked again by PCP or Urologist. otherwise, nothing to worry about.

I think you had urology work up for hematuria but I doubt if you also had kidney biopsy or genetic testing. A kidney condition called thin glomerular basement membrane disease, a congenital disease, can present with isolated microscopic hematuria but kidney fx is not affected. Or a female with Alport gene (X-linked) may have hematuria but does not have Alport syndrome; however, her son will.