Dwarf shrimp’s color is one of the most important quality criteria and dictates its market price. In the shrimp keeping hobby, a pale shrimp is not a competitive product. Therefore, a lot of aquarists ask these simple questions. How to enhance shrimp color? Can they improve the coloration at all? The answer is – Yes. It is possible.
The pigment of shrimp is dependent upon feed quality, water quality, and stress factors. Moreover, such environmental factors as a light regime, substrate, and background color also affect shrimp color.
In this article, I will refer to some biological studies about this matter. You will know facts about shrimp coloration and some more useful information about shrimp keeping hobby.
Without any further ado let’s get started.
Dwarf Shrimp Pigmentation. Astaxanthin.
In order to know how and why it is possible to enhance the shrimp’s color, we need to know more about shrimp pigmentation itself.
In shrimp, astaxanthins (a member of the carotenoid family) are the main pigments associated with external color. These chemical compounds (molecules) are responsible for the yellow, orange, and red colors in many shrimp and when chemically bounded with proteins they may extend their reflection wavelength to blue, green, brown, black, or violet color.
Note: In addition, besides pigmentation, astaxanthins improve survival rate and serve several other functions in shrimp such as:
- a source of vitamin A;
- increase weight gain;
- enhance the immune system;
- maintain ammonia excess and resistance to stress;
- improve the digestive system.
Interesting fact: According to the study, the pigmentation pattern is most pronounced in the anterior body parts (carapace) of the shrimp. Biologists found in all shrimp that the pigments in the carapace were larger and more dispersed than in the other regions.
Astaxanthin as pigments is important to shrimp and fish which are unable to synthesize pigments on their own and therefore have to rely on dietary supplements to achieve natural pigmentation.
Different experiments showed that astaxanthin powder will enhance whatever natural color already exists.
Biologist investigated the effect of dietary on pigmentation and growth of Red cherry shrimp (Neocaridina davidi). After the 8 weeks feeding trial, the results indicated that Astaxanthin-fed groups had significantly greater pigmentation than that of shrimp fed without it.
Note: In addition, Red cherry shrimp fed on diets with this component has greater weight gain than those of shrimp fed on diets without it.
Note #2: Astaxanthin is also a very powerful antioxidant which is added to many foods and supplements for fish, shrimp, and humans too.
1. Shrimp Food to Improve Color
So, now when we know what lies in the base of shrimp pigmentation. We can use it to our advantage. Color enhancing foods can be a really good tool to help improve the color of your shrimp. It is possible to buy a number of shrimp foods, which are intended to improve color.
As I have already said, Astaxanthin (check the price on Amazon and here) is an important part of shrimp pigmentation. Nonetheless, I need to stress it out that it can enhance whatever natural color already exists. That is why do not expect any miracles. However, in some cases, these changes can look like ones, even when we are talking about the same genetics.
Tip: Do not add too much. Use a very small amount for your shrimp.
DIY recipe with Astaxanthin powder
The recipe is called “Shrimp Kandy Feast” and all credits go to jayc and Michael Petro.
- 1 teaspoon of Agar-agar powder (2gm).
- 350ml water.
- Chlorella powder 3 teaspoons.
- 1 teaspoon Astaxanthin.
- Bee Pollen 1 teaspoon.
- Spirulina 1 teaspoon (optional)
Note: buy only agar that has no other additives like sugar, flavoring, or coloring.
- Add water and Agar-agar powder into a pot, and bring to a low boil.
- Stir constantly or the agar will stick to the pot. Keep the heat low to medium.
- Heat until all sign of the agar powder is dissolved (approximately 5 minutes on low-med heat).
- Pour into a shallow and flat container (for ease of cutting later)
- Let it cool for 4-5 minutes.
- Crush the bee pollen in a mortar & pestle.
- Then sprinkle in the Chlorella powder, Bee Pollen and Astaxanthin into the container. The agar would not have set yet.
- Mix all ingredients together.
- Let it set in the fridge for 30 minutes.
Arctic Copepods (link to check the price on Amazon) has incredibly high levels of carotenoids (astaxanthin, cryptoxanthin, echinenone) which will enhance the color in your shrimp. This is an amazing product.
TetraColor® (link to check the price) provides a sufficient amount of carotenoid pigments for the shrimp. Multiple studies reported an increase in Red Cherry shrimp body coloration with the inclusion of increasing amounts of carotenoids in shrimps’ diet. For example, the highest pigmentation tested was 200 mg/kg, whereas the carotenoid content of the commercial food used in this contribution was 382 mg/kg.
Hikari Shrimp Cuisine, Hikari Micro Wafers, and Hikari Tropical Crab Cuisine (link to check the price on Amazon) naturally offer higher levels of color enhancers, which help develop a true coloration. One of the main components of their food is astaxanthin. Balanced formulation offers necessary nutrients that promote proper shell development as well.
According to some results of the research, I quote “for pigment enhancement, blanched carrot, cucumber, dried grapes and mixture of commercial shrimp foods were administrated and results were encouraging”.
2. Dark Substrate.
A long time ago shrimp keepers noticed that black substrate is very important to bring out intense coloration. At the same time, if you put them back to the tank with a white substrate, the color fades away.
It can sound strange but by doing so they try to camouflage from predators. In shrimp, camouflage is considered the primary function of adaptation to different habitats and background, rendering the animal cryptic to potential predators.
Of course, you can exclaim that they are red (yellow, blue, etc.) and shine like beacons for the fish! How can they hide?
The point is that shrimp do not understand it. For example, in the wild, Neocaridina has a pale-brown or muddy-brown color. Shrimp breeders took away this defense mechanism. They changed their colors to red, blue, yellow, etc. However, shrimp acts instinctively by enhancing whatever color they have.
Biologists noticed that the total carotenoids (astaxanthins) in shrimp kept in black and red gravels were higher than those in white gravel. In addition, the weight gain of the shrimp significantly increased as the darkness of background color increased. Actually, it may be related to the color that best mimics the natural environment of the species.
3. Background tank color and Reflected-Light
In another experiment, the 30 shrimp were assigned randomly to 10 tanks (10 L each) under light conditions provided by a 65W-fluorescent lamp daylight color (6500 K).
The results of that study demonstrate that shrimp coloration can be manipulated by changes in reflected-light. The red color of the background induced shrimp to show a more red-intense coloration compared to the white one.
This is a cheap and simple way to enhance shrimp coloration. Therefore, it could make sense to sacrifice some system units and customize it to hold specific shrimp species.
Note: Researchers supposed that the same end result could be obtained either by using red-emitting light or adding red filters to white lights.
4. Dwarf Shrimp Age
Shrimp age is another aspect of body coloration. The point is that it will change with age. That is why do not judge too early and do not cull your shrimp until they are fully-grown (or at least when they are one month old). Shrimplets do not have an intense coloration as adult shrimp have. Color changes can continue for months!
According to some experiments, body coloration in 180‐day old Red Cherry females was significantly higher than in 90‐day‐old females, indicating that female coloration is strongly influenced by age. For example, coloration was 68.85% more intense in 180‐day old females than in 90‐day‐old females.
But what about males you can ask?
Biologists observed a slight increase in male coloration through time, although it was always lower compared to females of the same age. The authors considered that the accumulation of pigments was less since adult males of those species, as well as in Neocaridina davidi, are smaller and less colored than females of the same age.
5. Stress and Water Quality
Stressed dwarf shrimp can temporarily lose the color. Actually, stress can cause legitimate and very devastating health concerns for your shrimp. Because when the shrimp is stressed over a prolonged period of time it can actually cause them to break down and have diseases and succumb to things that they would normally be able to fight off with their immune system.
That is why hiding places or caves in the aquarium can also affect the intensity of coloration that your shrimp is going to show. When shrimp feel secure in their environment they are going to have the best chance of developing a really intense beautiful coloration.
In addition, shrimp are very social. They will never develop their full-color intensity potential unless kept in groups where they can interact with other individuals of their species and feel safe.
The last one but not the least, any shrimp or fish will look nice and healthy when they are in their optimal care requirements. Therefore, pay attention to your water quality (PH, GH, KH, TDS, nitrate, copper, etc).
Intense color is the most desired feature for the shrimp hobby, defining its trade value. Color is a fundamental component of the price tag and poorly colored shrimp command a lower price, reducing competitiveness.
Therefore, selective breeding of intensely colored morphs, usually preferred by aquarists, over the collection of wild specimens.
Although shrimp coloration is known to be affected by many factors. We can also influence and enhance it by following simple rules.
- Provide a sufficient amount of special food for the shrimp.
- Give your shrimp natural food.
- Use a dark substrate and background in your shrimp tank.
- Let them age. The older the shrimp the more colorful they become. Remember, that female coloration in 180‐day‐old females can be nearly 70% higher than in 90‐day‐old females.
- Keep them in good water condition.
- Do not let them stress.
- Chromatosomes In Three Phenotypes of Neocaridina denticulata Kemp, 1918: Morphological and Chromatic Differences Measured Non-Invasively. Article in Journal of Crustacean Biology 31(Oct 2011):590-597. October 2011.
- Assessment of potential trade‐off between maternal colouration and offspring quality in the ornamental “red cherry” shrimp Neocaridina davidi (Bouvier). Article in Aquaculture Research. March 2019.
- Effect of background color on shrimp pigmentation. Article in Boletim do Instituto de Pesca Sao Paulo 37(2):177-182. January 2011
- Reflected-light Influences the Coloration of the Peppermint Shrimp, Lysmata boggessi (Decapoda: Caridea): COLORATION ORNAMENTAL SHRIMP. Article in Journal of the World Aquaculture Society 47(5). June 2016.
- Effect of Dietary Astaxanthin and Background Color on Pigmentation and Growth of Red Cherry Shrimp, Neocaridina heteropoda. Vol 38 No 1 (2014): January-April.
- Quantifying pigment cover to assess variation in animal colouration. Andjin Siegenthaler, Debapriya Mondal, and Chiara Benvenut. School of Environment and Life Sciences, University of Salford, Salford M5 4WT, UK.
- Background color effect on the pigmentation of prawn Macrobrachium tenellum. Latin american journal of aquatic research. Lat. Am. J. Aquat. Res. vol.46 no.3 Valparaíso jul. 2018.