I also suspect that as a high transporter he should be prescribed Extraneal, a long dwell PD fluid that draws off fluid slowly and is used as a day dwell. I suspect that even though he takes phoslo, he still has a lot of phophorous floating around his body. Extraneal would help this as the fluid would stay there for a long time and have sufficient dwell length that it would be able to pull off this difficult to remove large molecule. I am not sure which clinic that your father attends. If it is Davita, they are very reluctant to prescribe Extraneal as it is expensive and it cuts into thei profit margins. They try to prescribe it only to diabetics, but it is indicated for all PD patients. We had to threaten their CEO with legal action before they would allow it to be prescribed to me, even though I had already been prescribed it before we moved.