The Crab Street JournalMilo K, Hermit Crab reading  The Crab Street Jourmal

 

Home: Articles  : Colour Enhancing Foods


Colour Enhancing Foods

by Vanessa

There are many ways to improve their colouring, from giving them hermie-friendly bark and driftwood to munch on, to foods such as FMR Land Hermit Crab Food and HBH's Hermit Crab Bites; and colour enhancing fish flake is safe to use with hermit crabs, with some varieties including marigold or plant sources high in beta carotene. I found a good article on colour enhancing:

Principles of Colour Enhancing Koi Foods

http://www.koikichi.com/about/articles/colour_enhancing_food.html

"Here are some key words to look for when considering dietary supplements that will enhance red pigmentation in your koi - carotenoids, canthaxanthin, astaxanthin, spirulina, Musca Domestica and Krill.

Carotenoids are a family of over 600 natural lipid-soluble pigments that are produced within microalgae, phytoplankton, and higher plants. They also produce compounds such as essential fatty acids, steroids, sterols, vitamins A, D, E, and K. Within the various classes of natural pigments, the carotenoids are the most widespread and structurally diverse pigmenting agents. They are responsible, in combination with proteins, for many of the brilliant yellow to red colors in plants and the wide range of blue, green, purple, brown and reddish colors of fish and crustaceans.

Carotenoids are absorbed in animal diets - sometimes transformed into other carotenoids, and incorporated into various tissues. As we all know, flamingo's are pink or should be pink - this is due to ingesting algae containing high levels of beta-carotene and then converting this yellow carotenoid into canthaxanthin and astaxanthin before depositing it into the feathers and tissues as red plumage. Some fish species such as koi and various crustaceans have the enzymatic mechanisms to convert carotenoids into other forms as well, such as astaxanthin - some fish/animals don't. Astaxanthin is the optimal carotenoid for the proper pigmentation of the red/pink colors is aquaria. Crustaceans and other aquatic animals are unable to produce astaxanthin de novo (naturally), only plants and protists (bacteria, algae, fungi) are capable of synthesizing carotenoids. Therefore astaxanthin must be available in either their native habitat or manufactured diet to meet nutritional requirements. In the natural aquatic environment, astaxanthin is biosynthesized in the food chain within microalgae or phytoplankton at the primary production level. The microalgae are consumed by zooplankton, insects or crustaceans which accumulate astaxanthin, and in turn are ingested by fish which then accrue astaxanthin.

Fish in the wild will obtain natural red, orange and yellow color pigments, via carotenoids, through natural food sources such as shrimps, snails, daphnia and blood worms. Pond's lack these natural food sources so the fish require a supplement to their diets. Unfortunately natural color enhancers are an expensive addition to a diet, so many fish foods do not contain them or they are provided in such small quantities they are not effective.

I personally feed a very high protein, low fat, low carbohydrate diet. For pellet food I usually use Hikari Excel, Hikari Hi-Growth, Hikari Wheat Germ . I use a paste food that starts out at 63% protein off the shelf. In that paste food I mix several different ingredients - Musca Domestica (common house fly) either the larvae, or I prefer the pupae as it floats better and is 55% protein. You can also buy Musca Domestica larvae that is 'gut loaded' with canthaxanthin and or spirulina. The spirulina I use is 60% protein with just 7% fiber. Freeze dried Krill which is a small shirmp-like member of the Crustacea family, is up to 70% protein. Krill are planktonic and feed on algae rich zooplankton where they get astaxanthin - up to 80-120 ppm of astaxanthin where your koi, at most, contain 5-8 ppm in their tissues. I like the fact they're freeze dried instead of using heat which can/does destroy some of the vitamins and fatty acids."

http://www.koikichi.com/about/articles/colour_enhancing_food.html

 

Summary/Main Points:

"Carotenoids are the most widespread and structurally diverse pigmenting agents"

"Astaxanthin is the optimal carotenoid for the proper pigmentation of the red/pink colors is aquaria."

"Crustaceans and other aquatic animals are unable to produce astaxanthin de novo (naturally), only plants and protists (bacteria, algae, fungi) are capable of synthesizing carotenoids."

"Therefore astaxanthin must be available in either their native habitat or manufactured diet to meet nutritional requirements. In the natural aquatic environment, astaxanthin is biosynthesized in the food chain within microalgae or phytoplankton at the primary production level. The microalgae are consumed by zooplankton, insects or crustaceans which accumulate astaxanthin, and in turn are ingested by fish which then accrue astaxanthin."

"Fish in the wild will obtain natural red, orange and yellow color pigments, via carotenoids, through natural food sources such as shrimps, snails, daphnia and blood worms"

ie. Crustaceans eat other crustaceans, plankton and algae in order to develop their colouring. They are unable to synthesize or process the colour enhancing carotenoids or pigment(colour) agents that increase their colouring.

If we feed our hermit crabs things like Krill, Blood Worms, Baby Shrimp, and Musca Domestica (common house fly) *shudders* along with the woods (and in some cases, Brown Oak leaves such as Carol offers Jon and Kate) high in tanine and pigments, then they will improve their colouring. I would hazard a guess that the roasted Nori sheets I give my hermit crabs (seaweed that is pressed into flat strips and roasted, to be used with Sushi) are high in carotenoids and astaxanthin, as would other types of algae I feed my hermit crabs.

While hermit crabs are not Koi, I thought that this introduction to pigment-rich agents and how crustaceans obtain their colouring would be helpful to some.

Happy Hermit Crabbing,

Vanessa