There should be little notches and bumps in/on the pipe to turn it to so it doesn't leak. I have had no problem with leakage and do not seal it. I take the pipe off the humidifier every night so it can air dry and once a week take it apart completely and flush it with a water/bleach solution. Of course I empty and rinse the humidifier daily - it might seem like overkill to some but I think it is too easy to "let it for a couple days" and end up introducing mold and/or bacteria into the cage. And we all know that I obsess 
I work from home so I do not have a set schedule for the humidifer - Luna just asks. LOL! well, OK, she doesn't quite ask but I sort of turn it on as the need arises. Like if she had a shower I don't put it on again until she is nice and warm. It is probably on a total of 2-3 hrs./day
Hope this helps 
lele
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0.1 veiled - Luna
0.2 felines - Kyndra and Líta
1.0 African Clawed Frog - Skipper
0.5 Mad. Hissers
0.1 Chilean Rose Hair Tarantula (no name yet)
0.1 Goliath Bird-Eater Tarantula - Natasha