Hi, new to the hobby and want to make a monofin. I have a pair of swimfins I want to turn into monofin but need advice. Im going for more of a dolphin shaped fin rather than fish. But to accomplish that i would need to pad it out a bit. I have the fins for propulsion but what material would be good for a more 3d dolphin fin shape? I have eva foam on hand as well as a few foam pool toys. Would that work or should i find something else?