Aquaman has control over all creatures of the ocean. Cthulhu is a creature of the sea (arguably). Can aquaman control Cthulhu? If not is it because Aquaman is not powerful enough or because Cthulhu does not count?
Although this power is most often and most easily used on marine life, Aquaman has demonstrated the capacity to affect any being that lives upon the sea or even any being evolved from marine life.
Cthulhu! I command you to do my bidding!