So I got my hands on a second hand redsea 300 g2+ and I am not going to be setting up the sump because I just don't have the space. Instead I am going to use the overflow box as the filter and return pump area like a all in one tank. What I need help with is figuring out what material the pipes in the back are made of so I can get the proper cement/glue to cap them off. I read somewhere that they are made of acrylic but that was just a single source. Can't find any other info about the material online so I turn to the other diy-ers for help. Thank you everyone!
