Pond/Water Feature Lighting? (UK)

Depends on your budget. Also, if I recall correctly, you’re in the UK, right? The available devices will be different there.

Here’s one recent discussion.

I think a lot of people use the Fibaro RGBW controller, put the controller indoors, and just connect it to whatever outdoor feature lighting you want to use. That’s probably the simplest and would be available for both the UK and the US.