heres the pic of my jacks

http://i234.photobucket.com/albums/ee103/necromancer4/DSCI0003-1.jpg

Jd's are named after a boxer and can live up to the reputation. However not all are. I have a jd that isnt aggressive at all and never has been. I have spoken to a few people who think the aggression has been (accidentally) bred out with certain breeders

If the previous owner says it killed other fish then you probably have an aggressive one tho.

Nice looking fish

well after about 5 months in there own tank i finally got the nerve up to try and introduce my 2 jacks into my oscar tank. the last time i tried this the male jack was constantly attacking my red and albino oscar(who were smaller than him at the time) and left the bigger tigers alone. now all the oscars are significantly larger than the jacks and things so far seem to be going fine.(a little chasing but i think they have to figure out living area).
now the press is on for the new tank because i think im overstocked in my main tank now. do you think 300 imp gallon tank will be big enough for my 4 oscars 2 jds 2 convicts a sucking loach and a rainbow shark?

so u do have a male and female i use to breed jacks to sell to the lfs my male was 9 inches and female was 7 inches oh and the way i tell between males and females are by the gill plates the female will have blotchie spots on the bottom of half the gill plates and the males spots will be on the top half in yur pic male is on left female is on right hope all goes well for ya

well about a week of harmonyous(sp?) living goes by and finally jack snapped. he is now constantly attacking my albino. he wont leave the poor thing alone and finally i had to put a divider in my tank. the funny thing is he doesnt bother any of the other fish in the tank (and there are some smaller than he is)only the albino. i thought it might be because hes mostly white but he leaves the pink convicts alone. so now im looking at getting another tank and rehousing some fish.(i quess there are worse thing than getting another tank )

so i took the divider out of my tank this morning to see if my jack would stop attacking my albino oscar. and in less than a minute he was at him again. needless to say the divider is now back in the tank.so i quess its off to the local fish store to buy another tank on thursday. i have had my eye on a 65 gallon tank and i think im going to get it for my pair of jacks. hopefully this will be enough for them to live the rest of their lives in and maybe even breed.