Hello, I recently purchased an Ultitube with D5 Next reservoir/pump combo (part 31400) (no leakshield, just the basic unit). I have been trying to leak test with a pressure tester before installing it in my loop but I find that it loses pressure quite quickly. It generally takes about 10 minutes to lose pressure entirely so it is not instant but definitely not considered air-tight. I have purchased a separate lid without the pressure equalisation membrane and am testing with that. I have verifie...