I bought a baby Oscar yesterday (5cm ish) along with 6 Platys. When they went in the tank (floated bags, added tank water to the bags, floated some more, added moretank water & floated some more before releasing) the platys all just went straight off on their way but they little guy dropped straight to the bottom. From what I've read that wasn't too suprising as they tend to "sulk" on the bottom after a change. After about 4 hours he was swimming around and looking good.

This morning all the platys are doing find but the little Oscar was dead on the bottom, he's been chewed on (eyes, fins & stomach are gone) so no way to figure out what happened but I'm thinking maybe overnight the Oscar dropped back to the bottom of the tank & someone (BGK) attacked him, but the thing is that my BGK is 4 years old 20cm and has NEVER eaten anyone before.

So my question is really - I have an in tank seperator (one of those boxes with holes that you can stick inside the mains tank to seperate off fish), maybe I could get another little guy & put him in the box until he grows bigger and gets comfy in the tank so he stops dropping to the bottom where he would be vulnerable.

What do you think?

Oh tank is well established 320L so it's not "new tank"
Occupants are:-
2 Plecos (10cm each)
1 Black Ghost Knifefish (20cm)
1 Redtailed Black Shark (10cm)
2 Penguin Tetras
added
6 Platys
1 Oscar (5cm)

ok it could be a few things, ph shock, temp shock if not aclimatised properly, my bets on the red tail black shark, they get realy teratorial and are very quick, unlike a small oscar who is pretty slow realy, plus its not realy wise putting oscars in with platys, as oscars like to eat platys and if your buying small oscars, only buy ones that look plump, if they look thin they are no good, they have not been fed properly and will be weak, its a good idea to buy more than one as they do like each others company, good luck mate.

I'm with karl. Red tailed black shark. All the sharks can be real B8stards, irrespective of what your LFS may tell you that it's only the blacks that are a problem.

kev

I have to agree with others too, Another sugestion is that when you bring new fish home instead of floating them try picking them up in a esky/bucket and when you get home put a air stone in and gradualy introduce your water into the bucket every 20mins to half hr. I find that doing this reduces stress and less chance of loosing them in my experience.

Cheers
Johno