A device and methods for treating renal failure are disclosed. One embodiment of the device is an implantable peritoneal dialysis device. When in use, the device can have a semi-permeable reservoir implanted in the peritoneal cavity. The reservoir can receive blood waste and drain through one or more conduits, via a pump, to the biological bladder. Solids and/or a solution benefiting dialysis can be pumped to the reservoir and/or implanted in the peritoneal cavity.