What are the tiny bugs in my saltwater aquarium?

Answer by  SunnyStars (836)

Most likely amphipods or copepods. Harmless critters (Invertebrates) that are present in most healthy saltwater aquariums. Overfeeding or under-filtering aquariums can cause populations to explode. Perform a partial water change to keep their populations under control. These tiny crustaceans are desirable. They provide fish with a natural source of livefood.

Answer by  Lisa86 (79)

Commonly known as sand fleas or water fleas. They are harmless bottom feeders. Some kinds of fish enjoy eating them.

Answer by  Nanthawat (131)

There are many microorganisms living in fish tanks of many types. You may be looking at brine shrimps that were possibly used to feed younger fish that were kept in the same tank as the fish you've purchased. Brine shrimp eggs can live for few decades before they are hatched.