Which settings to make underwater objects less blurry?

Maybe it's the monitor? I bought a gaming monitor with 144 Hz. I might replace it as the light colour is way too cool for me, and too bright, even with adjusted settings.

I just saw a screenshot by @mcrudd in another post of a mermaid in water, and the outline of her arms looked just like what I'm observing, though. So maybe it's just a nuance between different monitors, but the effect is the same.

And yeah, higher settings don't make it better, they actually make it worse ^^ Lower settings soften everything.