I am reinstalling an older single drain glassholes overflow and its leaking from the outside. From what I could gather one gasket goes between the overflow box and the aquarium and one goes on the outside. Thats how I have it right now but I've also seen people having two gaskets on top of each other between the box and glass. I see that they used to sell silicone lube with the kits so I think Im going to grab some of that in the morning and try it out.
Any other suggestions?
Any other suggestions?