I used Cassel's free scallop pattern tile 1 to make these fish. The scallop shape just reminded me of fish scales so I vector drew the fish shape, filled the body with the pattern that i had coloured with a gradient and then used a plugin from filters unlimited, colour rave - atmospheriser to get some colours going on. I also used the technique shown by Cassel in her monthly seminars using the select, modify, feather and brightness contrast technique to get some shading where I thought it might be needed. I then put them on a gradient background to simulate under the sea.
Sheila x
https://creationcassel.com/store/index.php?main_page=product_info&cPath=7_9&products_id=416