It depends really. It's one of those "length of string" questions.
I've written novellas that were between 10,000-30,000 words, while full-length novels are usually something like 70,000-100,000 words and I've never written one of those. The genre and writing style will also affect word-density. YA novels have smaller word counts than, say, cosmic horror stories which are famously very wordy.
Basically, they can be as long as you want. The length of your story should serve the concept, and shouldn't be dictated by a stranger who doesn't know all about your concept.
Also, episodes on Tapas are NOWHERE near the length of a chapter. Episodes on tapas are pages, not chapters.