Copepods & Amphipods
Found tiny white bugs in your tank?
What are they?
These tiny microscopic-like white bugs swimming or crawling all over your tank. What you are most likely seeing are Copepods and/or Amphipods. These are shrimp-like crustaceans that dwell in the substrate as adults, but during their larval and juvenile stages are most often free swimming.
Basic facts about these tiny crustaceans
So what fish and other marine animals eat copepods and amphipods?
Amphipods (Grammarids) are one of the main live food sources of adult Seahorses, as well as newly hatched fry. They will wrap their tails around something stable and then feast on them as they swim or float by.
So what do you do if your aquarium does not have a good bug population present to sustain these types of fish and you don't want to wait around until one develops, or their numbers are taking over the aquarium and you want to control or remove them?
How To Control or Remove Copepods and Amphipods
Even though considered a food source to some tank inhabitants, these bugs are considered no more than a nuisance to others. Sometimes when very large populations of these bugs are present in the free swimming larval and juvenile stages, you may see fish in the tank shaking or shuddering. This is because the bugs crawl around on the bodies of the fish, causing what you might explain as a tickling sensation that is annoying to them. This can become overwhelming and exhausting for the fish, because they find it difficult to get any rest as they constantly move or dart around to keep the bugs off of themselves.
If this happens and you are concerned about your fish, and you do not have any bug eating animals present in the aquarium to help reduce their numbers naturally, it may be necessary for you to take steps to control or thin them out. This can easily be accomplished by simply running a hang-on-tank type canister filter (read reviews compare prices) with a fine micron sleeve or pleat cartridge on the aquarium for a short period of time to filter the bugs out of the water.
Remember, these tiny bugs are a beneficial and natural part of a good balanced aquarium ecosystem, and an important food source required by some species to survive! They aren't really hurting anything, and unless they are causing a big problem for the fish or other tank inhabitants, you shouldn't have to do anything about them. Once they grow to maturity, they will retire into the rocks and substrate of the aquarium.