When picking a water feature you need to consider colour matching it with your patio. The Colour Wheel below is a useful guide to identifying colours which work well together.
When two colours are opposite each other on the Colour Wheel this is known as contrasting colours. For example: orange and blue or red and green.
When colours are close to each other on the Colour Wheel this is known as harmonising colours. For example: different shades of grey.
So for example if you have a grey slate patio you could pick a water feature that is a different shade of grey or you could pick a terracotta water feature which would be a contrast to the patio.
Some effective combinations are: