If you are willing to attach an external device to raise the humidity, consider this:
Install a mini float valve in the plastic container you saw in the Youtube video. That will maintain the water level and you don't have to refill it manually. You can DIY with the fogger and an ordinary bucket. The float valve is available from usplastic.com
If you make the tubing/ducting to the vivarium a bit larger and enclose the top with plexiglass, the fan will draw humidified air through it into the tank.
Oh, that's another interesting idea. Do you mean attaching the float valve to the humidifier or using the ultrasonic mister? Sorry, I'm having a bit of trouble visualizing it.
Just curious, is there any reason you wouldn't recommend the MistKing? It seems to be a pretty comprehensive system that could yield itself to further automation in the future and the price point the seller is at now would only have me spending a little more than the DIY options.
Mistking
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