Well, the water feature just became the least of my problems.
Late last night my wife noticed a tiny bit of water on the floor of the basement. She thought she spilled some water, but when she was wiping it up she noticed that more water rose up from between the tiles when she pushed on them. We went into the neighboring room where the HVAC system is, and sure enough, water was leaking out of the AC unit, going under the wall, and into the other room.
The first problem is the broken AC, but we're going to have that looked at. The bigger problem is the basement floor. We started at the wall and began pulling up tiles that had water under them, working our way back from the source of the water. We ended up pulling up around 3/4s of the basement floor. The flooring was a really shitty, super thin linoleum tile sitting directly on the concrete foundation. I've been wanting to replace it, so I don't really care about ripping it all out.
A couple questions:
1. Is the black discoloration mold or just discoloration? There's never been an overly musty smell in the basement, and it doesn't feel like mold (though I've never touched black mold before). We had a mold test done when we moved in and it was fine.
2. What kind of flooring would you suggest I put down?
Obligatory pics:
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