but will oscars live together ? or am i in for a blood fest?
I rescued a tankfull of fish a couple of months ago and it had two 7" albino oscars, one 7" tiger oscar, one 6" flower horn, one 5" jack demsey and 1 6" common pleco all jammed into a 29gal tank.
It was disgusting how dirty the water and gravel were. The fish didn't fight because they could barely turn around without bumping into eachother. I seperated them out with the flowerhorn, jack dempsey, and pleco in the 29gal and the flowerhorn immediately started to beat the crap out of the jack dempsey and pleco until I removed them. The local pet shop took the oscars in for me and sold them for $10 each. The flowerhorn can only live by itself but when crammed together in an overcrowded tank it was not as aggressive.
If someone told you that the fish wouldn't outgrow their tank then they lied. It's a common misconception. I have seen people here compare it to a man living in a prison camp in a 4 foot box for years. They can SURVIVE but that is not really LIVING... just existing.
If I remember rightly, the shark will get to several feet long. Not just 12''
The first link I provided says :
Origin:......................Fast flowing open waters of Thailand
Max size:..................40"
Min tank size:..........135 gallons
Its name of "shark" encourages aquarists to keep them but not more than 85% of them get bigger than 8" long in aquariums before they die. This is not a recommended aquarium fish.
I would at least give the shark back before you get attached to it so it doesn't have to suffer in your care (they will probably re-sell it to another unsuspecting person but maybe it will go into a 125gal or larger and you won't have to be the one to end it's life early)
PS. Have you read about cycling a tank yet? You may lose them both in a week or two when you get an ammonia spike if the tank hasn't been cycled properly anyway.
Just my two cents
-- itZme