The peppermint shrimp (Lysmata wurdemanni) is a nocturnal, omnivorous, saltwater invertebrate that lives in the shallow waters of the Caribbean Sea, the Gulf of Mexico, the East Atlantic Ocean, and in the coasts of Florida. It is usually found near the coral reefs and sometimes tube sponges because that is where it finds all of its food, along with very good hiding places.
The peppermint shrimp is considered a cleaning animal in a saltwater aquarium. As a matter of fact, they have become very popular in the last years because you actually have to work less cleaning the tank thanks to these invertebrates. Also, they are cheap, have a unique appearance, and they are very easily available.
The genus Lysmata (Peppermint shrimps) is one of the most heavily traded on the market because of their aesthetic value and ability to control aquarium pests (aiptasia). This species is very easy to find in aquarium stores and they cost from $5 to $10 US dollars.
Quick Notes about Lysmata Wurdemanni Shrimp
||Candy cane shrimp, Caribbean cleaner shrimp, Veined shrimp, Cleaner Shrimp|
|Scientific Name||Lysmata wurdemanni|
|Tank size (minimal)||10 gallons (~40 liters)|
|Size||4 – 5 cm (~1.5 – 2 inches)|
|Optimal Temperature||25 – 28°C (~75°F – 82°F)|
|Water type||SG = 1.023 – 1.025|
|Optimal PH||8.1 – 8.4 (7.5 – 9)|
|Optimal KH||8 – 12|
|Nitrate||Less than 20 ppm|
|Life span||up to 2 years|
|Color Form||Semitransparent with red longitudinal, transverse, and oblique bands around the body|
Description of the Peppermint Shrimp
This Lysmata wurdemanni is also called: “Candy cane shrimp”, “Caribbean cleaner shrimp”, and “Veined shrimp”. Some of its names are due to its colors. They have a semitransparent, creamy-reddish exoskeleton with red longitudinal, transverse, and oblique bands distributed around the body, a carapace with broad transverse and oblique V-shaped bands.
Note: When they become stressed out, they can lose some color and turn almost completely transparent.
It is a beautiful and brightly colored shrimp. When they are adults, they can measure up to 2 inches long.
They usually live for about 2 years. Therefore, it is better to buy young, small ones because the big ones might be close to finishing their lifecycle and they may only live for a couple of months.
Behavior and Temperament of the Peppermint Shrimp
The Peppermint shrimp likes to look for food at the bottom of the tank by sifting in the sand and walking on the rocks. It sometimes oscillates sideways while standing on the rocks.
This species is known as cleaner shrimp because of their feeding on external parasites on fishes. However, they are not that effective as, for example, Lysmata amboinensis species.
They usually get along well with other shrimp in the tank. Lysmata wurdemanni species do not have enlarged chelae (claws) and aggressive interactions are rarely observed even with other species of shrimps in the aquarium.
In general, it is considered a sociable and peaceful shrimp with the rest of the animals.
The peppermint shrimp is a shy, nocturnal species. It eats at night and instinctively hides from their predators during the day. So, do not worry if you have not seen it for a while in your tank, the peppermint shrimp is probably hiding in cracks and crevices.
Tip: If you use a flashlight with a red filter during the night, you will probably see it.
Peppermint Shrimp and Corals
Some aquarists say that the Peppermint shrimp are not recommended for a reef tank. The main reason is that they eat small polyps and soft corals. People who have put them in these types of aquariums in the past complain that they started seeing how the corral was getting nipped and had no idea what was going on.
However, there are also aquarists who have never experienced anything like that. Their Peppermint shrimp did not touch corals in the tanks at all.
How is it possible?
Actually, it depends on the Lysmata species. According to the study, even aquatic shops do not know what they sell. Unfortunately, it is very easy to confuse the Lysmata boggessi (the Atlantic Peppermint shrimp) and Lysmata wurdemanni (the Gulf and Carribean Peppermint shrimp). Unless you have a trained eye.
The Lysmata boggessi shrimp have semi-translucent reddish exoskeleton covered with narrow, longitudinal, transverse, and oblique pale red stripes. The carapace has V- and U-shaped oblique and transverse stripes. In addition, we can see a distinctive inverted Y on the carapace.
The Atlantic Peppermint shrimp (Lysmata boggessi) are NOT reef safe. Several of these shrimp can tear up a few corals within a night.
The Peppermint shrimp (Lysmata wurdemanni) are reef safe. They will not attack corals. So, do not make a mistake when you are going to buy one.
Molting of the Peppermint Shrimp
Like all invertebrates, they molt (shed the shell/exoskeleton) to grow. The smaller they are the more frequently they molt. Peppermint shrimp are very vulnerable during this process and stay hidden to avoid any predators.
Tip: Do not throw away the old shell. They will eat it later to restore calcium in the body.
Peppermint shrimp need adequate calcium supplement and trace minerals in the molting process. I highly recommend reading my article “How to Supplement Shrimp and Snails with Calcium”.
Feeding Peppermint Shrimp
The Peppermint Shrimp is omnivorous. They feed on food debris, detritus, dead fish tissue, and organic material in decomposition, etc. It is one of the types of animals that are used to clean an aquarium.
It is easy to feed them because they usually look for food in the aquarium on their own and they might not require a lot of extra food. However, you can add a piece of fresh fish or a sinking shrimp pellet every now and then. Depending on the size of your tank and the amount of fish in it, you might not have to feed it at all.
They are amazing for eating Aiptasia (glass anemones), which are considered a pest in saltwater aquariums because they reproduce quickly and sting corals and fish. Sometimes the Peppermint Shrimp will only eat the smaller anemones and ignores the big ones.
Tip: If it is your case, it means that they are not hungry enough and have something else to eat in your tank. If your intention is to include the Peppermint shrimp in your aquarium to get rid of the Aiptasia and it is not doing its job, you can add more of these shrimps in the tank.
Some commercial diets to make your Peppermint Shrimp happy (links to Amazon):
Peppermint Shrimp and Body Pigmentation
To improve and maintain body pigmentation of your shrimp, make sure that you include carotenoids (astaxanthin) into their diet.
Besides enhancing the coloration of the Peppermint shrimp, astaxanthin improves survival rate and reproduction, due to their antioxidant activity and their contribution to the neutralization of free radicals in the cells of the organism.
According to the study, in addition to the survival, the presence of carotenoids in the diets of the Peppermint shrimp promote rapid growth.
Tip: The variation of the background color, such as the intensity and type of illumination in the tank, will also play its role. Peppermint shrimp have a constant concentration of body pigments which they express to a greater or lesser degree depending on the environmental conditions in which they live.
Keeping Peppermint Shrimp
The Peppermint shrimp are very easy to take care of and very undemanding. Therefore, they are widely recommended for beginners. Although this species can adapt to a lot of water conditions. There are some things that have to be considered.
They like aquariums with live stone, hiding places, and open places to search for food. You need a 10-gallon aquarium for two of these shrimps and 5 more gallons for every additional Peppermint Shrimp you add to the tank.
Ideally, Peppermint shrimp should be kept in a group because when they are alone, they get stressed. If you follow the rule about having one Peppermint shrimp for every 5 gallons of water, they should do their job well and have enough space for themselves.
There are just a few things that have to be considered in order to prolong the shrimp’s life and make it a positive part of the aquarium. The most important rule you need to remember is that, like all shrimp, the Peppermint shrimp prefer stability. They do not like changes.
The temperature of the water should be between 25 – 28 C (75 and 82 F). The specific gravity required is 1.023 – 1.025. The pH needs to be between 8.1 and 8.4. The carbonate hardness has to be from 8 to 12. It also needs a water filter and water pump. They do not tolerate large ammonia and nitrate level. Be very careful with copper.
They do not require any special preference regarding substrate. The species was reported to occupy multiple habitat types from rocky shorelines, hard-bottom reefs, tube sponges, to shell bottoms within inlets.
There should be also some plants, which can be real or fake. The aquarium should have the light turned on during the day and turned off during the night.
Mating Peppermint Shrimp
Peppermint shrimp (Lysmata wurdemanni) are protandric simultaneous hermaphrodite. It means that all individuals first mature as a male (male-phase) and then later change to a female (female-phase – FP) that spawns and broods embryos but can also mate as a male.
They have a remarkable capability of copulating and inseminating as males on the very night in which they themselves undergo a spawning molt and copulate, as females, with another FP. Mating experiments confirmed that Lysmata wurdemanni females are capable of mating as a male or as a female with subsequent spawning of eggs. They are, however, incapable of self-fertilization.
Note: In the wild, rates of sex change are highest from late winter through spring, in time for the spring–summer breeding season. According to different studies, there is no evidence to support demographically (male and female ratio) influenced and socially mediated (density) environmental sex determination.
The change of sex from male phase to the female phase normally occurs at 2.40-2.60 cm (~ 1 inch). However, in some cases, the size and age at which sex change can be even at 1.5 cm length (0.6 inches).
Breeding Peppermint Shrimp
This species has a larval development in which metamorphosis can last from 38 to 67 days. Each female can carry up to 300 eggs (green ovaries).
The Lysmata wurdemanni female shrimp carry the eggs for about 10 – 12 days under their abdomens. Within 12 hours of the eggs hatching, they molt, may mate and then spawn. This is the only window during each molt cycle that a shrimp can mate.
In case you want to help the larvae survive, remember it is very difficult to succeed at this.
The optimization of feeding regimes during the shrimp larval rearing process should be your number one priority. For example, according to the experiments, biologists used four different diets:
- Arfemia nauplii,
- rotifer Brachionus plicafilis,
- microalgae Chaefoceros gracilis
- Isochrysis galbana.
The larvae fed with Chaetoceros or Isochrysis only survived for a maximum of 17 days. However, the survivorship of the larvae fed with Artemia nauplii or rotifer was almost 70%. Nonetheless, with Artemia nauplii larvae grew significantly faster (reached postlarvae in 29-32 days) compared to rotifer (reached postlarvae in 32-36 days).
Arremia nauplii were also tested as potential food for the postlarvae and juveniles. All survived to reach sexual maturity in 50 to 70 days.
The larvae can become food for corals and small fish in the aquarium. This is why it will be better to take special care of these larvae in a separate tank. It should have an air pump with a small aquarium filter with a sponge.
Tip: Light attracts Lysmata wurdemanni larvae. Lure them to the corner with a flashlight or desk lamp. Use a 10 ml plastic syringe and 5 inches of airline host in the end to catch the larvae. Do not use mesh. Even a fine mesh can hurt the larvae.
Peppermint Shrimp and Tankmates
By putting together animals that get along in the same tank, they will all live longer and better lives. There are some species of fish that get along really well with the peppermint shrimp. Gobies, dragonets, tetras, grunts, and filefish can be great tank companions.
As part of the care that these shrimps should have, it is important to know which animals not to include in the same tank, because this shrimp has predators. Some of the animals that prey on the peppermint shrimp are the wrasse, coral banded shrimp, and any fish bigger than 6 inches long.
Lysmata wurdemanni species (the Peppermint shrimp) is among the many cleaner shrimp that are popular with aquarists, because of their coloration and the ease with which they can be kept in captivity.
The care that the Peppermint shrimp requires is minimum and you can get as interested and involved with this species as you want.
The peppermint shrimp (Lysmata wurdemanni) is a very interesting type of shrimp. They can make the life of any person with a saltwater aquarium a lot easier because it does the cleaning. It is a beautiful shrimp, sold at a reasonable price.
- Growth, survivorship, life-span, and sex change in the hermaphroditic shrimp Lysmata wurdemanni (Decapoda: Caridea: Hippolytidae). Article in Marine Biology. July 2003
- Protein and lipid requirement for the growth and reproduction of the peppermint shrimp Lysmata wurdemanni. Article in Aquaculture Research. May 2019
- Simultaneous hermaphroditism in the marine shrimp Lysmata wurdemanni (Caridea: Hippolytidae): an undescribed sexual system in the decapod Crustacea. Marine Biology (2001) 139: 1155-1158 DOI 10.1007/s002270100679
- Reproduction in a simultaneous hermaphroditic shrimp, Lysmata wurdemanni: any two will do? By Lin, D. Zhang
- Effects of Food and Temperature on Survival and Development in the Peppermint Shrimp Lysmata wurdemanni. JOURNAL OF THE WORLD AQUACULTURE SOCIETY Vol. 29, No. 4 December, 1998
- Not any two will do: DNA divergence and interpopulation reproductive compatibility in the simultaneous hermaphroditic shrimp Lysmata wurdemanni. Article in Marine Ecology Progress Series .August 2009
- The effect of astaxanthin and β carotene inclusion in diets for growth, reproduction and pigmentation of the peppermint shrimp Lysmata wurdemanni Article in Latin American Journal of Aquatic Research · July 2019
- Matin behabiour, epibiotic, growth, and the effect of salinity on grooming activity in the hermaphroditic shrimp Lysmata wurdemanni. Dissertation by Tuhin Giri. 2003
- The effect of background colour and lighting of the aquarium on the body pigmentation of the peppered shrimp Lysmata wurdemanni. Article in Aquaculture Research. August 2018
- Baeza et al. (2017), Integrative taxonomy of the ornamental `peppermint’ shrimp public market and population genetics of Lysmata boggessi, the most heavily traded species worldwide. PeerJ 5:e3786; DOI 10.7717/peerj.3786