I dropped by a LFS and saw a tank of JD's and light blue colored fish that were also labeled as JD's. I asked them to be certain and they said indeed they were JD's. Is this correct, I didn't know they could be pure blue as babies?
Blue JD's??
- Thread starter paradigmcubed
- Start date
Blue JD's are quite new in the hobby, well new in the sense they have only been around in the last 10 years. They ARE NOT a hybrid dispite what you may hear some say. They are true dempeys that were in bred numerous times to get the final blue color.
They are a nightmare to keep. Very weak immune systems.
There's a nice post going on about them over at aquamojo explaining just about everything that you wanted to know about them.
Here's a link: http://208.51.130.220/~mojo/cgi-bin/yabb/YaBB.pl?board=CA_SA;action=display;num=1043330935
There are 2 types of blue on the scene right now the veil/fan tails, and the regular finned blues.
I actually started a breeding experiment with some veils that failed miserably. All the fish come to me with gill flukes and never really recovered. The immune system was just too weak.
I just bought some regular finned blues last week and this summer I am going to attempt to restart my breeding project. These ones seem to be in better shape and much stronger that the veils from last year.
They are a nightmare to keep. Very weak immune systems.
There's a nice post going on about them over at aquamojo explaining just about everything that you wanted to know about them.
Here's a link: http://208.51.130.220/~mojo/cgi-bin/yabb/YaBB.pl?board=CA_SA;action=display;num=1043330935
There are 2 types of blue on the scene right now the veil/fan tails, and the regular finned blues.
I actually started a breeding experiment with some veils that failed miserably. All the fish come to me with gill flukes and never really recovered. The immune system was just too weak.
I just bought some regular finned blues last week and this summer I am going to attempt to restart my breeding project. These ones seem to be in better shape and much stronger that the veils from last year.
Thanks, are these usually more expensive than usual JD's. I went into a Petsmart to get some guppies, never buy fish there, however they had two of these and now I'm tempted considering they are $2.99
theyre quite a bit more expensive than regular JD's. ive only seen 2 for sale in my area and they were going for $40.00 apiece. there is no mistaking them for regular JDs. they dont even look like the same fish. $2.99 would be a steal.
Yeah, they really didn't look like JD's, but now that I've seen a pic they are the same fish as the ones in the pet store. I would guess the price difference is because they probably just get a load of JD's in a shipment, the employees may not know any better and price them at $2.99
hey at 2.99 a piece u cant go wrong. at my LFS they had 1 at 59.99 i almost bought it but since i have an overstocked tank i didnt buy him. 
From what I have read about them I got the impression that you can't get them to breed or their fry all die. My understanding of it is that the guy who breeds them has dempseys with the recessive blue genes in them and it works the same way as albinos(genetically). I don't think anyone that has dempseys with the blue gene would sell them, because then the price could be driven down or they would lose business to others.
I'm not completely certain about this though.
I'm not completely certain about this though.
the way blue depmseys come out:
-there are two jack dempseys.
-if one of the JDs has blue recessive genes some fry will be blue JDs
-fry hatch.
-some of fry are blue JDs (if blue genes are present) they blue JDs are weak fish from the start. when they grow up they are either eaten by other maturing JD fry or just die from not enough food. is comparison JDs are about 3x aggressive as Blue JDs.
if u want to breed blue JDs you need 1 JD or blue JD with the recessive blue traits and 1 with out them, (not all blue JDs have the recessive gene and there is no way to decipher if the do from the outside (same for jack dempseys too)) if u have 2 blue dempseys and they breed you should get a sterile brood and have no blue JDs.
Hope this clears up some of the foggyness out there. there was a past thread on this that i explained this b4 but i couldnt find it and didnt look 4 it.
-there are two jack dempseys.
-if one of the JDs has blue recessive genes some fry will be blue JDs
-fry hatch.
-some of fry are blue JDs (if blue genes are present) they blue JDs are weak fish from the start. when they grow up they are either eaten by other maturing JD fry or just die from not enough food. is comparison JDs are about 3x aggressive as Blue JDs.
if u want to breed blue JDs you need 1 JD or blue JD with the recessive blue traits and 1 with out them, (not all blue JDs have the recessive gene and there is no way to decipher if the do from the outside (same for jack dempseys too)) if u have 2 blue dempseys and they breed you should get a sterile brood and have no blue JDs.
Hope this clears up some of the foggyness out there. there was a past thread on this that i explained this b4 but i couldnt find it and didnt look 4 it.
While it is possible albeit astronmically hard get a blue dempsey from a 1st generation batch of fry. The odds would be about a billion to one. After all it is the recessive gene. Both parents would have to have this gene to make the fish blue in the fisrt generation. Hence the odds.
Some 1st generation regular/blue fry may have a little more blue than others but that does not make it a blue dempsey. Afterall all JD's have some blue in them
The reason blues are so weak is due to the constant inbreeding that has been and still is going on.
Granted with time and when they have been around long enough and there is enough different broods that eventually survive, you maybe able to breed them true. But right now it can't be done.
If you breed a blue with a regular it will take roughly 2 to 3 generations of cross and breeding back and forth before you get any visable blue fish. At least a fish that you could call a blue dempsey.
Example:
2 breeding pairs A/B and X/Y mate each pair has 1 blue and regular parent.
In the 2 broods of resulting fry roughly 25% of them have the recessive blue gene.
To make a stronger blue you would now have to breed A/B brood with the blue from X/Y and vise versa.
Now these broods generation 2 will have roughly 50% of the fry with the recessive gene.
Cross breeding the gen2 broods with either of the original blues you will get baby blue dempseys. That's generation 3. But you will still have a genetically weak fish. Although probably allot stronger than what is on the market right now. That is assuming that you get the 2 original blues from different sources.
Some 1st generation regular/blue fry may have a little more blue than others but that does not make it a blue dempsey. Afterall all JD's have some blue in them
The reason blues are so weak is due to the constant inbreeding that has been and still is going on.
Granted with time and when they have been around long enough and there is enough different broods that eventually survive, you maybe able to breed them true. But right now it can't be done.
If you breed a blue with a regular it will take roughly 2 to 3 generations of cross and breeding back and forth before you get any visable blue fish. At least a fish that you could call a blue dempsey.
Example:
2 breeding pairs A/B and X/Y mate each pair has 1 blue and regular parent.
In the 2 broods of resulting fry roughly 25% of them have the recessive blue gene.
To make a stronger blue you would now have to breed A/B brood with the blue from X/Y and vise versa.
Now these broods generation 2 will have roughly 50% of the fry with the recessive gene.
Cross breeding the gen2 broods with either of the original blues you will get baby blue dempseys. That's generation 3. But you will still have a genetically weak fish. Although probably allot stronger than what is on the market right now. That is assuming that you get the 2 original blues from different sources.