Japan Blue Guppies Galore

Japan Blue Guppies Galore:

In this post, I am gonna share with you guys my experience with a strain of Guppies known as the Japan Blue Guppies or also known as the Aquamarines.Tank of Japan Blue Guppies

Out of a line of Galaxies, it happened that a Japan Blue guppy came out from a batch of young. It became the first strain that I managed to fix. My thoughts is that the Galaxies were crossed with the Japan Blues to improve the Galaxy’s iridiscents and sheen. If I am not wrong, the Japan Blues characteristics are quite dominant and I guess some breeders might have figured out that they could improve another line’s colour and brilliance and in this case the Galaxies by out crossing them with the Japan Blue strain.

Why are they called Japan Blues, you might ask.

Most people say that the fish was developed in Japan, hence the name. I wouldn’t be surprised if they were actually bred in Japan. My perception of the Japanese in fish breeding is that they take what they do seriously and be quite meticulous when it comes to the details of doing things and achieving their objectives. I am not saying that other nationalities lack this sort of punch but the Japanese have shown that they can produce good fishes.

Japan Blue Guppies

Anyway, let me tell you more about the Jap Blues. When I first got the male Jap Blue from the Galaxies, I managed to cross it with its sister which happens to be a female Galaxy. The resulting F1 turned out to be approxiamtely a 50-50 ratio of Jap Blue males and Galaxy males. From this batch, I chose a Jap Blue male and crossed it with its sister and continued doing this. By F3, I managed to fix the Jap Blue line. All the Japan Blues that came out from here onwards looked quite similar in terms of colour and size. Most however, did not have a good dorsal size and shape and this is one area that could be worked on if I had enough tanks and space.

One interesting thing to note is that there were no physical or colour difference between a female Galaxy guppy and a female Japan Blue guppy. I find this really interesting and was wondering whether the Japan Blue guppy characteristic only shows in the males and not the females, thus explaining this occurence. I suspect that this could be the case as the female Japan Blue guppies really looked identical to the Galaxy guppy female in terms of size, shape and colour. Simply amazing.

The finnage of the Jap Blues are average in my standards. One characteristic that needs to be improve is the size of the dorsal. Nevertheless, selective breeeding efforts did pay offa s can be seen in the picture below. I managed to improve the dorsal fin to a certain extent. Improving a few fishes finnage is one thing, getting the whole batch looking that way is another. That is why the challenges of Guppy breeding keeps me coming back to this hobby. 🙂

Let me conclude, I find that Jap Blues is a hardy line and breeds prolifically. They grow to a large size and is one of the easier strains to keep. It will make a good strain to start with as it is not as demanding as the other strains that might be a lil bit picky in terms of providing them the best kinda conditions.Japan Blue Guppies looking bright.

Do give the strain a shot if you happen to come across any. They are not that easy to find nowadays but you do find them once in a while. It is always good to try to keep some of the strains that you are not used to keeping as you will get the opportunity to learn something new about the strain and their genetic make up. Guppies do throw surprises once in a while and it is these kind of moments when you get a nice surprise that makes you feel that the hobby is worth it.

For me, I will continue to look out for new strains for me to keep and experiment with. It gives me the kick to try out new strains and having them swimming in my tanks.

PS: I have found a Jap Blue line with blue body and pink tails. More about this guys. I am outcrossing them to another strain to see what happens. Stay tuned!!!

~ Ardy

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  • Where did you find your Japan Blue Pink tail? I have those. I found them in a local petstore and grabbed them right away.

    I have 3 strais of Japan Blue: Grass, Wild High Dorsal & Pink tail.

    Can you post a picture of your pink tail?

    This site is very informative.

    Thank you

  • Ishykiel

    Hi FP,

    I got the Japan Blue Pink tails from a local fish farm. I think that these fishes can be developed as the fishes that were in the tank looked very similar to each other.

    You might need to get a more established Japan Blue strain to cross with in order to get those Pink tails that you want.

    I will try to get a picture up of the pink tails soon.

    Happy Guppy Keeping!

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