Just because a critter lays eggs in your aquariums, doesn’t mean those eggs will hatch. Oftentimes, invertebrates will lay eggs onto a smooth surface or broadcast them into the water. These eggs haven’t been fertilized, and would require a concerted effort of male and female spawning activity in order to be fertilized. This behavior is very common among corals and snails for example, and could lead to the false hopes that you have a spawning population of some random invert in your aquarium. Despite not resulting in captive breeding in your aquarium, your fish and corals sure will enjoy the snack.