I had to revive this thread after reading all the translated chapters...
6000
Would be an incredible horror series, I'd say "I'd prefer" a live action movie, but it's too long of a story to fit into movie format, and I have yet to see a live action series (longer than 6 episodes) convey (this type of) horror. As an anime, this would be a genuinely scary series for me, something I've only felt with "Ghost Hunt". "Another" just wasn't scary for me in any way, "Shiki" was close, the beginning was really strong, but then fell short, same for "Ghost Hound". If I am forgetting stuff, it's because it didn't strike me as scary.
Here "In a certain part of the Philippine sea lies the deep-sea residential facility Cofdeece. This large facility, located 6,000 meters below the surface, was closed after a "certain accident" that, combined with maritime territorial disputes between Japan and China, caused the facility to be abandoned for some time.
In the year 201X, and investigation into weather or not the facility could be activated has begun; however inexplicable things began to happen one after another..." (I cut off a bit of spoiler)