Calculate an initial dialysis prescription (Rx), based on goal spKt/V

67 year old African American male with history of diabetes, hypertension, and advanced chronic kidney disease has been initiated on dialysis in the hospital. He has received 6 treatments so far and has done well without significant issues with hypotension or cramping. He will now be transitioning to your outpatient dialysis unit. The patient weighs 70kg and has a well functioning AV fistula.
How would you calculate the initial dialysis prescription based on goal spKt/V?