New tank mate aggression!

so I got a stalsbergi the other day on impulse at Denny's Pet World.

It has been fine, no signs of any aggression until this morning. I have LOTS Of hiding places in my tank, and i rearranged the tank when i put him in, so i was hoping he would get along without too much damage. he is the same size as my Jag, and probably 30% bigger than my three festae, so its not like hes the little one in the tank... Anyway heres a pic, you can see the bite mark on top of him.

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And here is the tank, lots of driftwood!

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I think my midas got a hold of him... but the festae i put in a week ago have no damage anywhere. Is there any way to mitigate the aggression?

No not really. You have plenty of room, and fish seem small. I have fish every day in my grow out tank, that appear with marks like that. I wouldn't worry.

You say your Midas may have done it, but at the top you didn't say that you had a MIdas. How big is it?

His 120 stocklist is in his sig.... I would say, you have a lot of heavy hitters in that tank and I hope you plan to split that into two tanks around that size in time. Aggresion happens with cichlids, its inevitable, most of the time everything finds its "place" in the pecking order and tank in general. But I have heard of fsh that simply will not live with anything else. So I would just keep a watchfull eye, and rearange the tank every so often.

oh my tank list is in my signature. the midas is about 5.5" now. he was 2" when i got him at the end of august...

you can see his nose just to the left of the chopstick with a broccoli stem on it, hes behind the driftwood.

(i only suspect the midas because he killed two pictus catfish)

Tank gets rearranged every week. I remove almost all the decor and the put it back in different spots. Most of my fish are still quite small, the Midas grew a lot faster than i was hoping and is easily the biggest. I am moving them(or most of them) to a 300+ when i move out of this rental next spring.

I do plan on dropping 3-4 of the fish when i upgrade though. (for example, i only want one festae, the last thing i need is a breeding pair of anything to murder everything else i the tank )

Lol yeah, breeders can be killers. Cool that sounds much better that 300 will be ill. I overstock but I dident know if you had plans for that to be your final stock. Lol.

Ya I guess thats why you guys put your lists there. DAAAAAAAAAAAAAAAAA!!!

It could be many things. It is a new fish, so everything will get after it. Because the Midas is so much larger than the rest, it is already (most likely) the top dog in the tank. So in my experience with large Cichlids is, if the top dog does not feel threatened he will ignore the new additions. I find that its the fish next in line in the pecking order that cause issues. So I would say that its the Jag or Con or Dempsey. Just keep an eye on everything, it should calm down. As for re-arranging the decor. That may work, but when ever I do that, my fish either just follow the decoration around the tank, or they control one area of the tank, regardless of whats there.

I know what it is, the midas wants me to catch him being an ass so he gets put in the "time out" tank full of neons!

That could very well be it.

ok funny story!

i just threw in some nightcrawlers. The midas had one in his mouth and my poor abused stalsbergi stole it and hid under a piece of driftwood.

The new guy always gets beat on. Until he figures out he is not that small...

madness wrote:As for re-arranging the decor. That may work, but when ever I do that, my fish either just follow the decoration around the tank, or they control one area of the tank, regardless of whats there.

I have observed this behaviour as well, but only in adult fish 2+ years old or breeding pair, I have never seen it with unpaired sub adults or juvies. Not saying it can't or hasent happened, I have just never seen it. It seems the adults or pairs will pick a spot to defend in the tank regardless of what it there, or a specific "thing" they call home for a reason. Useually if its the location its something like, when fed the food is taken here by the current. And with an object its useually something like, the most ideal place for fry, or hiding. I saw this to be the case with my firemouths when they were with my jag, there was a small spot that they could go into and the jag couldent get to. So no matter where I put the skull they liked that was where they went and what the defended. No matter what you should try everything you can think of to try and redirect that attention somewhere else. And it sounds like you are trying and hopefully you will find success. Good luck.

I notice too that tank size can have a huge impact on the way fish act. I moved from a 120g (60x18x26) to a 210g (72x24x29) and noticed a difference in the way the fish act. My Midas is pretty mellow but he would still get into a mood and chase my silver dollars like crazy. Now in the larger tank he barely even exerts the effort to chase. Having the extra space really helps.