This is Sea Devils 2, published by Mimosa (SA Magazine Co) +/- 1963-1964.
It reprints the cover and story from DC Comics' Sea Devils 9 (1963):
"The Secret of the Coral Creature!"
Also reprinted is this story from DC Comics' House of Mystery 37 (1955):
"The Water World"
32 pages, glossy colour cover, black and white newsprint interior.
Here is the cover of issue 2 and DC Comics' original cover: