Electric Blue Jack Dempsey Color change?

[Stinson Beach Aquatics]

Hello all!

I have an electric blue Jack Dempsey (3 inches or so) that I’ve owned for a few months now. When I first got him, he was a pretty standard bright turquoise blue (as seen below). However in the past month or so, I’ve noticed he has turned much darker and spotted. For anyone who has experience with electric blue jack dempseys, is this normal? Is he just growing up or could he potentially have something going on? The reason I ask is because I have another tank that is currently being treated after identifying a fish that had callamanus worms. Other than the possibility of equipment transfer, they have no contact with the other tanks.

In terms of the darker coloration on the EBJD, most pictures I see online more closely matched his appearance as a younger juvenile than now. What do you think? Perhaps the gradual change in color is nothing but I wanted to ask. He is eating like crazy, plenty active, and seems to be at a good weight. Tank parameters are in check ( Ph: 7-7.5, nitrites: 10, nitrites/ammonia: 0, temp: 78). Food is frozen brine shrimp, bloodworms, and mysis shrimp. I tried integrating beef heart into his diet but he didn’t seem to be a big fan. He is currently being housed with a couple of plecos and is doing great otherwise (with the exception of his newfound passion of destroying the aquascape). As a first-time EBJD owner, I just wanted to check in with some others who have more experience.

Thank you!

*photo 2 was about a month ago and the first pic was from this week

 

[Toby_H]

I'm a sucker for Blue Dempseys...
I have a 6~7" male now...
I've raised a handful well into adulthood... My Avatar pic is a mated pair that I had for 7 or 8 years... I bred them with very limited success over a decade ago...

In my experience, as fry they are pale powder blue, then powder blue then more brilliant blue (like in your bottom pic)... Then they go through an ugly stage as they hit the equivalent of teenagers. Then come out of that into their mature colors, which can vary in a decent range.

So I don't think your color change is out of the norm.

That said... They are known to be susceptible to parasitic infections. White stringy poo is the first and most obvious sign. I ran UV Sterilizers on grow out tanks when I was trying to breed them. It certainly helped (they require a very slow flow rate to be effective against parasites). I'm not the most knowledgeable when it comes to medications. That said, I personally wouldn't treat until I saw signs that I needed to treat. Obviously continue to avoid cross contamination between your Blue's tank and the affected tank.

 

[A201]

I've raised a few Blue Jack's too.
I think your Dempsey is normal.

When buying a juvenile fish fresh from the hatchery, there's a possibility that the fish has been fed color enhancing food, or maybe even juiced.

If that's the case, the artificially created vivid coloration begins to fade once the fish is shipped away from the source.

 

[danotaylor]

To my knowledge there’s no color enhancing foods for the blue spectrum, but the “juicing” theory is definitely plausible for sure. Juicing doesn’t create color, it enhances the potential. What I mean by that is juicing a regular JD will not make it look like an EBJD. Hopefully as your EBJD matures it’s awesome color will return!

 

[Stinson Beach Aquatics]

I've raised a few Blue Jack's too.
I think your Dempsey is normal.

When buying a juvenile fish fresh from the hatchery, there's a possibility that the fish has been fed color enhancing food, or maybe even juiced.

If that's the case, the artificially created vivid coloration begins to fade once the fish is shipped away from the source.

Interesting. I never thought of that but it wouldn’t surprise me. That’s good to know!

 

[Stinson Beach Aquatics]

I'm a sucker for Blue Dempseys...
I have a 6~7" male now...
I've raised a handful well into adulthood... My Avatar pic is a mated pair that I had for 7 or 8 years... I bred them with very limited success over a decade ago...

In my experience, as fry they are pale powder blue, then powder blue then more brilliant blue (like in your bottom pic)... Then they go through an ugly stage as they hit the equivalent of teenagers. Then come out of that into their mature colors, which can vary in a decent range.

So I don't think your color change is out of the norm.

That said... They are known to be susceptible to parasitic infections. White stringy poo is the first and most obvious sign. I ran UV Sterilizers on grow out tanks when I was trying to breed them. It certainly helped (they require a very slow flow rate to be effective against parasites). I'm not the most knowledgeable when it comes to medications. That said, I personally wouldn't treat until I saw signs that I needed to treat. Obviously continue to avoid cross contamination between your Blue's tank and the affected tank.

Thank you so much for all the great info. I really appreciate it. I had no idea that they went through a “ugly phase.” They do seem to be an interesting fish! I don’t know if I’ve ever had a fish with more personality before. He’s been very fun to have.

 

[jeaninel]

My EBJD did the same thing. Beautiful as a little youngster, darkened up later then became beautiful again at full maturity. He lived for 7 years. Passed away last year at 8" long. I sure do miss him/her. Here are some pics at various ages.