We should blur out the stem of each of the flowers, selecting the Turbulence Tool in the Liquefy window (the blurring can be done, using a big size brush. After that we may select a brush of small size to correct the thickness of the stems).

Underwater Dance

Merge down the layer containing the flowers, decolorize them and move off the black color out of the picture, applying Image ? Adjustments ? Selective Color.

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Insert on a new layer, above all the layers, the texture of the water.

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Create its reflections horizontally and vertically and minimize the color's intensity, applying the next command: Image ? Adjustments ? Hue/Saturation (ctrl+u).

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Change the layer's type on Overlay.

Underwater Dance