chocolate betta

Chocolate Bettas: What Makes Them Unique?

Betta fish come in a rainbow of different colors. Some even have a beautiful metallic sheen to add to their glory. Add to that the male betta’s characteristic trailing fins and many different tail forms. It’s easy to see why these stunning little fish are one of the most popular aquarium-kept species around today.

At the time of writing, it’s true to say that one of the most sought-after colors of betta fish is described as “chocolate”.  But that wasn’t always the case.

Now, it’s true to say that there is much confusion around concerning the chocolate betta. What exactly is a chocolate betta? What genetics cause the fish’s unusual coloration? What’s the difference between the chocolate betta and the “MG” or “pineapple betta?”

In this article, we seek to answer these questions for you, as well as providing more information about these eye-catching bettas.

What is a chocolate betta?

A chocolate betta should appear rich brown, although most have a pronounced orange or yellow hue to their coloration. The fish’s fins should be yellow or pale golden.

Recently, the term “chocolate” has been used to describe a brown-bodied betta that has yellow fins. However, this color combo is also described by the late Walt Maurus in his well-respected book on bettas as “brown/yellow bicolor,” rather than chocolate. 

That particular color combination has been around for many years. However, the variant has only recently gained popularity when an enterprising breeder began marketing the fish as unusual “chocolate” bettas. 

The chocolate betta is similar to the “Pineapple” betta. A Pineapple betta is primarily yellow in color and has scales that are outlined in black. These forms of betta are officially categorized as a non-red variety. 

However, the Pineapple betta is a phenotype that’s produced by the NR-1 mutation on the black-scaled, extended red betta, whereas the chocolate betta appears to be a true bi-colored variation, like the more commonly seen “Mustard Gas” betta. Where the Mustard Gas betta has a blue or green body, the chocolate betta seems to be the result of the NR gene working on black, producing a black/yellow (brown) phenotype.

Breeding Chocolate Betta Fish

The Genetics

As far as genetics are concerned, modern chocolate betta fish are homozygous for the recessive non-red, or yellow, gene. These fish also carry at least one other regular dark gene. 

Homozygous is the word that refers to a specific gene that carries identical alleles on both homologous chromosomes. The homozygous gene is referred to by two capital letters (XX) indicating a dominant trait, as well as two lowercase letters (xx) for a recessive trait. 

If you mate a chocolate betta with another chocolate betta, you should produce either all chocolates and perhaps a few pure yellow fish too. 

Crossing a chocolate betta with a solid, non-metallic iridescent fish should produce multi-colored fish in the first generation, all unseen recessive traits aside. That’s because the first generation of bettas should show normal red, together with the iridescence that the parents carry genetically, even though they don’t show them phenotypically, i.e., the fish’s physical or biochemical characteristics.

Chocolate Bettas x Melanos: An Experiment

An interesting discussion among betta enthusiasts is what would happen if you were to breed a melano and a chocolate betta. That’s a logical question, based on the assumption that the non-iridescent chocolate fish would reduce the iridescent fault in the melano, while still producing a fish that is very dark in appearance. 

Some breeders have experimented with breeding melanos and chocolate bettas with some intriguing results.

Initial Results

Because melanos are homozygous for the recessive melano gene, a first-generation spawn did not produce any melanos at all. That’s unsurprising unless the chocolate fish also carries melano genes. Similarly, the spawn produced no NR-1 yellow bettas, as the melano father did not carry the recessive NR gene.

The results were 100% multi-colored bettas. Using two males with impressive fins from that first spawning, the breeder produced more multi-colored bettas, together with some chocolates, melanos, and some melanos that were homozygous for the NR-1 gene. The melano is probably related to a variant of red. As a result, the mutant gene caused a dilution of the melano effect by blocking the gene’s development. Thus, the spawn produced black bettas that were slightly more dull in appearance.

As the majority of the melanos were not homozygous for NR-1, not all of the fish in the spawn were affected. The darkest males in the spawn showed a high proportion of red when viewed under the light, which would indicate that they did not carry the NR-1 recessive gene.

Next Step

With that in mind, the breeder who was carrying out the experiment faced a dilemma. Should they use the darkest male, which was most likely a non-red carrier? Alternatively, should they select one of the paler melano males from the same spawn to try to improve the color through selective breeding after isolating the NR-1 gene?

In the end, the breeder selected the darkest male with the least iridescence. This choice hung on the hope that successive sibling crosses would boost the number of melanos carrying the NR-1 gene.

Conclusions Drawn

It seems apparent that most yellow and chocolate bettas carry genes for the dominant extended red. The yellow color is actually a suppressed red that the NR-1 causes. If you are using a chocolate betta to introduce the yellow gene to your spawn, you will also get extended red as part of the deal. 

That’s because the chocolate betta you’re using will also most likely carry the extended red gene. Otherwise, the betta’s fins would be clear in appearance, rather than yellow.

If you cross a chocolate betta with a yellow betta, you will produce 50% yellow and 50% chocolate spawn. That is as long as the chocolate betta also bears the gene for Cambodian or non-black. However, if the chocolate fish does not carry the Cambodian gene, you will probably get all chocolate bettas. All of whom will be Cambodian genotypes.

Therefore, they will produce a few yellow bettas when crossed with a yellow. The same will result if crossing with another chocolate betta that carries the Cambodian gene. If the chocolate betta does carry a Cambodian gene, you should get a fifty/fifty chocolate and yellow split. Each of the offspring should be homozygous for Cambodian. 

What does a perfect chocolate betta look like?

Chocolate betta fish should ideally have a dark or light brown body and solid yellow fins. The fish’s body should not show any iridescence, and the fins should not have a variegated or butterfly pattern. If a betta is extremely dark so that its body appears to be almost black, that is not a good chocolate betta.

Similarly, a betta that has excessive blue or green iridescence across its body would most likely be more appropriately classified as a green/yellow or blue/yellow bicolor, or even a multicolor when warranted.

Although chocolate bettas are popular among amateur breeders and hobbyists, the International Betta Congress (IBC) does not officially recognize chocolate as a color. Instead, the brown body/yellow fin combo is classified as a dark-bodied bicolor for IBC showing purposes. 

The name “chocolate” is simply a strain name that is used to describe a particular color variant. In the late Walt Maurus’ highly informative and interesting book, “Bettas: A Complete Introduction,” which you can find on Amazon.com at this link, the author describes the chocolate betta as a plain, solid brown fish with or without black edges or the freckling of melanophores on the fins. 

According to Maurus, those chocolate bettas behaved genetically in a very similar way to the melano. That leads breeders to speculate as to whether the original chocolate color was an offshoot of the mutant melano gene. Interestingly, when the book was written back in the 1980s, the chocolate betta was considered to be a rather plain brown fish by most hobbyists. There was little interest in breeding or owning these unusual and attractive bettas.

Final thoughts

The chocolate betta is a rarely seen color that’s caused by several genetic quirks and selective breeding. 

The IBC has not officially recognized the chocolate betta. In fact, it was once spurned as rather drab and boring in comparison to it’s more gaudy cousins. But now the chocolate betta is a popular and sought-after strain.  Plus, it looks set to remain so for many years to come. 

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