Wow! Glad you posted this as yet another 'hidden' factor in the decision process.... much better to know all this upfront.
Your photo and details are also interesting because I was planning on same or similar bottle as an external collection container, so let me see if I've got this...
[*]You're venting the dampness to the walmart bottle which then vents to the outside of your cabinet. But you are not using the bottle for collection? Only to trap the dampness
The container is also collecting skimmate, the excess foam and air travel out of the collection cup into the container which has an air hose so that the air continues to outside the cabinet.
[*]You clean the collection cup and tower routinely but not the walmart bottle
Also empty the excess skimmate / foam from Walmart container, once a month or so.
[*]You've created an intake air 'vent' with the flex tube so as to collect air from outside the cabinet. Is that being overcautious or did you also experience damp air from it? Seems like the intake would only be sucking air as long as water is being pumped into the skimmer.
I only added the intake pipe because I didn't want any of the moldy air from the cabinet to get in the skimmer, I'll prob remove it now it's all dried out.
[*]Whey doesn't the skimmate enter into the walmart bottle? Is that because you are cleaning the collection cup before that happens?
[*]Regarding the external setup, can you post pics that also show how you are returning the water to the sump?
Will do in a few...
[*]How high is the water in your sump? Is the EV-120 elevated or at the same level as the sump's bottom?
It's an EV 240, and the whole skimmer is raised as the drain (from the skimmer) needs to be above the sump wall (unless you drill the side of the sump). The skimmer drain can only travel horizontal or downwards (not up) and if you put the drain return under the water you need to create a siphon break (as I have done), simply by adding a T section of PVC
with the top open to the air and the bottom into the water, I will send a pic of this too.