do i need to use pvc glue on the piping for my overflow, my new tank is drilled & i have the bulkhead fitting that goes through the glass, but i wasnt sure if i need to glue the suction & return piping that go up into the tank

thanks in advance for any help

could you possibly post a photo of your setup? The best thing to use is a silicone sealant. Okay, it may not be quite as strong as some other adhesives, but its flexible which is good because the pipes may get moved slightly occasionally. And more importantly, is very water proof which is very important when you are dealing with a lot of pipework. Have you got chambers inside the tank that the water flows into and then goes out a hole in the bottom of the tank? If so, we just put a liberal amounts of silicon sealant and no leak occurred.

yes i have chambers in both back corners & that is there the pvc piping is, i will try & get some pics now

before you use any pvc glue on your intake from the tank be sure to check and make sure it is safe for fish. i know there are a few different types of glue and there coded by colours.