What did you agree to in your building contract? Lighting is one of those things decided upon early in the beginning of the construction process. Easy to add then, very difficult if not impossible to add later. We had a simple 3 LED lighting plan and ended up with a dark spot (not as bad as yours - created by our shallow tanning ledge which was on one far end), but there were no practical ways to fix this after construction. Steps and shallow ledges do funny things with lighting.

its a good thing to build a pool ..thank's for informations

This is one of the reasons we began using nicheless LED lights about 12+ years ago.

The lenses are smaller and are set closer to the surface in multiples to provide as even of light distribution as possible.

We have not installed as "standard" wet niche light as shown, in the same time period on new builds or renovation projects.

Your set up is something we see quite often. The illumination probably would have been better if the lights were placed on the pool ends facing each other.

You could add the nicheless lights, but it requires core drilling into the pool and digging behind the pool wall/patio to do this. In short, an expensive and messy job.

We have on occasion sleeved under a patio to a grassy area or planter area but there is a risk of hitting pool pipe, conduit or the rebar in the wall.

If possible, remove the red filters to allow the brighter white light to reflect off the side of the pool and, perhaps, reduce the size/darkness of the dead zone.

There are no filters on these lights. The light rolls through a series of colors you program or you can hold it at one color if you like. The LED fixture allows for this.

I don't know the color of the interior surface, but a light colored surface illuminates the best.

Darker surfaces absorb colors. We do not recommend to our clients the color option when using darker plaster finishes. A white light is the best choice. Same holds true for any fiberglass or vinyl surface with dark finishes.