I downloaded a mod that improves the look of water (from ponds to the "ocean", and maybe bath water.
but in this hood shot the ocean is (GASP!) BLACK. I know for the pond water to be fixed you have to put 2 squares of a POOL to make it work. But am I supposed to do this by the ocean too? HOW?

Is it Voeille's mod you are using? Should work in hood view without doing anything, but if you are on a lot then the sea water, like the pond water, may require that you do a square of pool.

If you're on the lot, placing a pool tile should help (if you get weird water reflections on-lot, a pool tile in each corner fixes it).

If not, you likely have another shader mod that conflicts with Voeille's mod. There are a few that include the mod (sometimes with modifications), possibly some lighting hacks.

This can also happen if you install some shader mod which comes with several files in the zip and you're supposed to pick one based on what other mods you have. If you don't realise this and just install all of them, you get weird effects like this.

PK thanks; I don't know what I have or did...
And this is a hood view, not from the lot

So which mod are you using, and which files do you have installed?

I HAD 2 things installed: "Pool Water package", & "Sea Water package" - I found they are both from Voeille. The download says a square of POOL water is required on a lot to be able to see the corrected sea water from that lot. It also says that from hood view the "sea water is also changed".
So something is wrong..my picture is a HOOD view of the sea..which looks black

Do you have anything else that affects shaders- for example, Criquette's Better Nightlife mod, LazyDuchess Shader fixes, Niol's water colours?

If you've done anything to the sky (sky box, etc.), the ocean could be reflecting it.

Some lighting mods use Voeille's mod, an edited version, or a different version of an ocean/pool shader, so you'll want to check this too. Dreadpirate's mods in particular.

Are your reflections on in graphics settings?