'still Life'
I think the "pool" is actually a metaphor for his dark side. When he looks at the pool, he uses it as a mirror. Yeah, he can stare at the depths too, but his own reflection is also there. So when the guy looks inside the pool, he actually looks into himself. The dephts of his psyche. And he certainly has suicidal feelings in there. He uses the pool as a mirror to his inner self and he takes the suicidal feelings from there. That's what I think anyway.
Overall, an excellent song. Very underrated too.