Shark's just attacked several fish! Help?!?

[beercan]

Hi guys, my red finned shark has been living happily in my tank for about 4 months alongside some swordtails etc and all of a sudden, he/she's attacked and almost killed a female swordtail, and killed 2 neon topfeeder thingies (name unknown)

Is this normal behaviour for this fish? I was told that the red finned ones were placid, and red tailed ones nasty...?

Also, what do you guys do in a situation like this? The shark's in a breeder net right now to stop her attacking anything else...

Help please???

 

[abstract]

from what i've read red finned sharks (rainbow sharks) can become as terratorial and aggressive as red-tailed sharks....now that it has turned agressive it is unlikely to stop...i recommend returning it to the store for credit

 

[daudy_dojo]

what size tank is it?! cause sometimes depending on the size and how many fish redfinned sharks can go on a killing spree! my mom had some a while back in her 50 gallon ... but she was also so over stocked... then the next thing she knew there were a bunch of fish dead!!

maybe it wants to mate lol but yea how many hiding places are there for him? is it heavily planted?? all that jazz?

 

[daudy_dojo]

sorry double post

 

[beercan]

It's heavily planted one end, clear the other. It's a 4ft tank, and it's not overstocked I don't think...
3 Kribs, 1 Malawi, 10 Neons, 1 kissing Gourami (the other died after the survivor went for it), a Plec, a little plec, a swordtail male and female, 2 neon topfeeding thingies.

 

[daudy_dojo]

hmm how many gallons and what are the size of the fish!?! i havent really heard of a redfinned shark going on a killing rampage unless it feels threatened and i know they an be territorial but thats to bottom feeders and other sharks ... right guys???

 

[WILDER]

Sharks need a very big tank, also can you post water stats in ammonia,nitrite,nitrate,and ph.

 

[daudy_dojo]

also can you post water stats in ammonia,nitrite,nitrate,and ph.

that would help

 

[George Farmer]

1 Malawi

Never heard of a Malawi cichlid in the community before - I would have thought would cause more trouble than your shark.

 

[mlee0332]

did you actually witness the shark doing it or you just assume?

 

[beercan]

I'll post some figures tomorrow, but for now:

1. Yes I saw it doing it.
2. 37gal / 140 litres.
3. The Malawi was sold by Pets @ Home as a Kribensis, and when I questioned it looking a tad different I was assured it was the same. When it was in the shop's tank it was dull and therefore did look very similar. To be fair to it, it hasn't caused a single problem, and is very peaceful. Maybe that's cos there are no others like him?
4. The neons are normal neon tetra size, the kribs are 2" each, the shark is about 3"-4". Nothing big at all in there...

 

[sylvia]

You are just going to have to re-home it. RTBS are a little more aggressive than rainbows/red-finned but realy you encounter the same problems with both species. I suspect the problem is that it doesn't have adequate territory as the cichlids in the tank and plecs too will be occupying the same area and need territories of their own so this shark, which is only now maturing, feels threatened and attacked the swordy as a result. Your fish may not be large but you can still have conflicts between them - particularly as most are territorial in the lower layers of the tank. Besides re-homin/returning the fish, you could also just try densely planting or adding more hiding places but there is no guarantee this will solve the problem so it might not be worth the risk.

 

[Torrean]

I am not trying to insult your intelligence because I am sure that you are right and the rainbow did in fact attack and kill your other fish. But my rainbow sharks often clean my gourami's. I was very worried when I first saw this, but the gourami's showed no stress and made no attempt's to get away from the rfbs' so I let it be. I thought about it and I think that he was not attacking but cleaning the gourami.

First of all am I wrong, second of all is this possibly what is going on in your tank,.

 

[beercan]

Thanks.
I'm going to try some new hiding places and see how we get on...

 

[abstract]

um, i don't really think it was cleaning the gourami....more like eating its slime coat would be my guess....i really don't think rainbow sharks are cleaners, like some saltwater fish are...