Many types of shrimp have been successfully kept by saltwater aquarists. Some species are kept primarily for their beauty or fascinating behaviour while others are kept chiefly in order to help with aquarium maintenance by devouring algae, left over food and other types of debris. A few examples of shrimp species commonly kept by saltwater aquarists are Fire shrimp (Lysmata amboinensis), Pederson Cleaner Shrimp (Periclimenes pedersoni) and Peppermint shrimp (Lysmata wurdemanni).
Shrimps are found in the infraorder Caridea in the order Decapoda and occur in freshwater, brackish water and saltwater world wide. The order currently contains about 2000 described species. Animals in other orders will often have the word shrimp in their common name without actually being considered true shrimps, e.g. the so called opossum shrimps of the order Mysida and Lophogastrida.
In everyday language, the terms shrimp and prawn are often used interchangeably or applied to animals based on size rather than species. Scientifically speaking, true shrimps are the species found in the infraorder Caridea in the suborder Pleocyemata while true prawns belong to the suborder Dendrobranchiata. Both belong to the order Decapoda. The main difference between shrimps and prawns are the structure of the gills; shrimps have lamellar gills while prawns have branched gills.
As mentioned above, shrimps are not only kept for their beauty, they can also be very helpful when it comes to maintaining a saltwater aquarium. Fire shrimps (Lysmata amboinensis) will for instance help you keep the water quality up by continuously removing detritus and debris from the aquarium. They are also known to set up cleaning stations where fish will gather when they feel the need to have dead tissue and parasites removed.The Fire shrimp is a social creature and should ideally be kept in groups consisting of 2-3 specimens. They are also hermaphrodites and any two individuals are therefore capable of forming a breeding pair.
Fire shrimps are not the only shrimps that can help your fish combat parasites in the aquarium by removing external parasites from fishes and devouring them. The Pederson Cleaner Shrimp (Periclimenes pedersoni), also known as Anemone shrimp, is just one of many excellent cleaning shrimps that can be easily kept in marine aquariums. This shrimp will hop onto fish and pick away any visible parasites, and some fishes will even open their mouths and let the shrimp go in to clean out mouth-parasites. If you have anemones in your aquarium, the Pederson Cleaner Shrimps may enter mutually beneficial relationships with them. The shrimp will live among the protective tentacles of the stingy anemone and the anemone will be regularly cleaned from left over food and other types of debris.Peppermint shrimp (Lysmata wurdemanni) can be a great addition to an aquarium if you are having a problem with Aptasia. Aptasia, also known as rock anemone, is a brownish anemone that can multiply rapidly in marine aquariums and encroach on the corals. This can lead to coral mass-death. Fortunately, Lysmata wurdemanni is a sworn Aptasia foe that can help save the corals.