Question for the Old Timers, experienced not necessarily Old. (Innocent grin)

[AquaWoman]

So I’ve been keeping Discus for 4 years now (only killed one), I’ve been keeping tanks of fish (Marine and freshwater) for almost my entire life (I’m old) I’m also a chicken Farmer, so I understand pecking order dynamics.

Anyhow, I started a YouTube channel years ago and I keep getting the same questions about “Killer Discus”. What I think is happening is people new to the species are misinterpreting natural cichlid behavior. I have researched this including going through my library of vintage Discus books from Wattley and Axelrod etc. and they never mention Killer fish.

My own Discus have fought from day one ( Small 1inch juvies ) now my biggest is 7+ inches and they STILL fight, they still corner the smallest but all do well, all get food and there is no problem.

And yet, I get these same questions about killer fish trapping fish in the corner and they starve or get beaten to death. So any input on this would be appreciated. Does this happen? Is it rare? Or are they just witnessing the typical pecking order and misinterpreting it?

Thanks in advance for any info and incite given.

AquaWoman

[danotaylor]

It is natural cichlid behavior but not in a natural cichlid environment...the old song "nowhere to run too" comes to mind...the fish in the bottom of the pecking order simply have nowhere to escape as they would in the wild...the end result is killer discus (cichlids)...the glass cages we keep our fish in, even the biggest of them, are still minute territories when compared to the wild environment...in 35 years of fish keeping I have seen cichlids of every temperament maim &/or kill other fish in territorial defense/establishment. Most recently I had a new group of 8 x 5-6" discus in a BB 125. Everything was fine until a pair formed and had wigglers at one end of the tank. I went out and came home 3 hours later to a dead discus that had evidently ventured too close to the wigglers...

[RogueDiscus]

Hi Amy,
Congratulations on your success over the years. I'm reluctant to reply because I've never see this, but maybe that's the point. We know about normal pecking order behaviour, so I wonder what else is going on. Maybe the group wasn't big enough, 6 is often recommended as a good minimum, so that the low man was too exposed. Also, I imagine if a fish is getting sick for some reason (poor husbandry?) it might be getting singled out by the group. Just my thoughts.
Will be interesting to hear what others say.
Steve

[AquaWoman]

It is natural cichlid behavior but not in a natural cichlid environment...the old song "nowhere to run too" comes to mind...the fish in the bottom of the pecking order simply have nowhere to escape as they would in the wild...the end result is killer discus (cichlids)...the glass cages we keep our fish in, even the biggest of them, are still minute territories when compared to the wild environment...in 35 years of fish keeping I have seen cichlids of every temperament maim &/or kill other fish in territorial defense/establishment. Most recently I had a new group of 8 x 5-6" discus in a BB 125. Everything was fine until a pair formed and had wigglers at one end of the tank. I went out and came home 3 hours later to a dead discus that had evidently ventured too close to the wigglers...

Thanks for the input!
I too had a breeding pair in a community tank, a small one too, 65 gallons. The male was aggressive and kept the other Male away. I put up a divider to to see if that would increase the pairs chances of successful breeding but they ate the eggs.
Anyhow, that didn’t give me the same experience that you described. Can you be certain that the death was from another Discus and not something else? I’ll be very interested in hearing from others as well.
Thanks !

[AquaWoman]

Hi Amy,
Congratulations on your success over the years. I'm reluctant to reply because I've never see this, but maybe that's the point. We know about normal pecking order behaviour, so I wonder what else is going on. Maybe the group wasn't big enough, 6 is often recommended as a good minimum, so that the low man was too exposed. Also, I imagine if a fish is getting sick for some reason (poor husbandry?) it might be getting singled out by the group. Just my thoughts.
Will be interesting to hear what others say.
Steve

Hi Steve,

Thanks for the reply. I too wonder if there might be extenuating circumstances in these killer Discus cases.
It’s definitely an interesting topic and one I’m hoping we can get a reasonable consensus on.
Thanks!

[brady]

Hi Amy
I to have had discus a long time and other then a little dominance here and there I have never
had a discus killed by another. If some folks have experienced this they might want to look into
there tank conditions, ect.
BTW, where do you live in Ct. I live in North Granby.
Jay

[CliffsDiscus]

Yes, there are killers. They pick on smaller fish
kill their mate and fry. I give these Discus away. Some breeders say the results of aggressive gene.

Cliff

[brewmaster15]

Hi Amy,
I Agree with Cliff here. I have had a few and have one right now. If I place this male with any female other than his current mate he will literally beat her and chase her to death. Even his current mate takes some domestic violence. This male is a wild blue.

I had a red white that was just as bad.. it would spend 24/7/365 a year chasing and fin nipping. I ultimately could not keep it with any other fish and euthanized it.

Its not common out there.I think most of what people see is typical cichlid sparring and chain of dominance type aggression.

Al

ps.. you know I clearly remember when I thought others were old timers not me!

[AquaWoman]

Interesting. An aggressive strain maybe.......hmmm. Hopefully we can get more input from members, the bigger the pool the better the data kinda thing. Is this a more recent phenomenon? None of my books mention anything other than typical cichlid behavior. Mine are supposed to be Stendkers but since I bought them via a local store I can only take the seller’s word for it. My two Males fight constantly and there is some fin nipping and the occasional swollen lip and scale damage but never more than that. I am curious how they could physically manage a quick kill?? What would that look like?

Thanks all for helping out. And anyone else.....chime in please!

Jay,
Hi neighbor! I’m in Hartford county, rather not be more specific than that online. Thanks for your info.

[AquaWoman]

Cliff, would one particular strain have this gene or is it a recessive gene across species?

Thanks.

[LizStreithorst]

I had it just once and I've kept and bred Discus since 2001. I'm old in years as well. In my case it was a female that was the killer. She would terrorize every fish in the tank except her chosen man. I posted about her in a contest thread from a while back. She committed suicide not long ago while she was in a breeding tank with her chosen man. It about broke my heart. I have a bunch of her kids of different ages that are excellent so I guess I got what I hoped for from her. Still, loosing her hurt. She was special to me.

[AquaWoman]

I had it just once and I've kept and bred Discus since 2001. I'm old in years as well. In my case it was a female that was the killer. She would terrorize every fish in the tank except her chosen man. I posted about her in a contest thread from a while back. She committed suicide not long ago while she was in a breeding tank with her chosen man. It about broke my heart. I have a bunch of her kids of different ages that are excellent so I guess I got what I hoped for from her. Still, loosing her hurt. She was special to me.

Sorry you lost such a well loved fish. I’ve gotten quite attached to mine as well.
I’m actually a little surprised to learn that these killer fish do in fact exist, even if rarely.
Do you know how she actually physically killed the other fish? Were they starved? Bitten, battered and beaten? I’m curious as to how they accomplish the actual act of killing.

Thanks Liz!

[LizStreithorst]

She never killed. I took her out before she had the chance. I saw that she was biting, battering and beating every dang fish in the 120 long. She was fearless! The other fish were terrified of her.

She was a true beauty, too. How could I not have fallen in love with her.

[AquaWoman]

She never killed. I took her out before she had the chance. I saw that she was biting, battering and beating every dang fish in the 120 long. She was fearless! The other fish were terrified of her.

She was a true beauty, too. How could I not have fallen in love with her.

Well that to me sounds like normal aggression. Perhaps I’m just used to living with aggressive fish. Mine fight constantly but they are all healthy in spite of the occasional fin nips etc. Do you believe that if you hadn’t removed her she would have killed the others or just harassed them daily?

[LizStreithorst]

I think that wanted to kill. It was a large tank with 3 males and 3 females. She probably would have worn herself out first. She didn't know that she had to concentrate on trapping one fish in the corner and killing it before she moved on to the next one. May be that is normal aggression in a male, but it's unusual behavior for a female.

At the moment I have her husband in with his young sons and daughters. One of his sons, a breeding male. and he are best buddies. That's unusual. I'm sure that things will change if ones from later spawns declares herself to be a female.