Dave Bonta's short poem imagines a slow, heavy pull downward, and a speaker tempted to give in to it. The opening line says that all light must sink into a hole, which makes darkness feel like a natural law rather than a choice. The odd image of "walking fish" adds to this. Fish out of water are clumsy and out of place, so the picture suggests something worn out and dragging itself along, as if even light has grown tired of the effort.
In the second stanza the speaker turns to their own situation. The descent would be "easy" and "leaden," two words that pull in different directions: easy because there's no resistance, leaden because it's heavy and dull. The final line, "should I let go," is left open, so we don't know what the speaker will do. The mood is quiet, weary, and a little dangerous. The poem doesn't say what letting go means, but it makes the temptation to stop struggling feel very real.