I used some older Crackerbox Stamps for this for this cards. Some of the products I have used have been provided to me from various companies I design for. Affiliate links may be used in the links provided below.
I used some background paper (Funky Fossil Designs). I colored the fish with Copics and fuzzy cut them. Stamped the sentiment in the middle and arranged the fish around it. Added some white highlights.
The stamps I used: