Furniture grade PVC: If it's NSF rated, it's fine. The stuff you linked NSF rated isn't, and it's probably fine, but I'm a "peace of mind" prioritizer.
Fittings: A lot of saltwater people do SCH 80 grey fittings instead of matching the pipe color. It isn't stronger like some claim, but it does look better than white in most set ups.
Uniseals on glass: a big NO. It stresses the glass too much, especially if the hole wasn't edge ground and polished. What size bulkhead fittings do you need? Check these out: https://www.glass-holes.com/1-1-2-Bu...0sxs-short.htm
They're available elsewhere too, their site just had nice pictures.