Hi,
I am trying to carry on with my delayed setup and now I am struggling with the this. The bulkhead from the overflow box itself is fine and not leaking after filling the overflow with water for few days.
I filled the aquarium with tap water for leak test and no leaks from the fittings below the bulkhead until i start closing the gate valve (diaphragm valve) then water will start leaking from the joint socket where its connected to the bulkhead.
I tightened it with hand and did not use excessive force to tight it.
I tried again after applying teflon tape to the bulkhead and still seeing drops leaking after I close the gate valve
I have recorded a small video to show the point where the water will start leaking
Appreciate your feedback. Not sure what to try next
https://drive.google.com/file/d/1YFsczLUlslWpyAbBYp1CIcwOg4pyPM0s/view?usp=sharing