Trippingpara;2068113; said:Sounds like you have ABS pipe (which is black) not PVC pipe. The ABS pipe is two very thin layers of plastic molded over foam - hence the floating. Most people that I know with "black" pvc have white pvc that they painted black with Kyron Fusion spray paint which is supposed to be fish safe.
stevietennis;2068728; said:From what I heard ABS pipes can leak chems into your tank. I don't know if it is true or not but that fact that there is some possibility of it happening keeps me away from them. Good luck.