Okay, so we need to talk about aggression. We are dealing with cichlids here so even the least aggressive species will be pretty aggressive. You need to be aware of this and plan ahead. Cichlids have a lot of quirky characteristics that can be down right strange and unpredictable. Cichlids can kill each other in a matter of seconds.
They may be buddies one day and fight like cat's and dogs the next day. If you have two cichlids together and bought them as juveniles they 'usually' get along great but as they mature they get more and more aggressive and the whole world changes for them.
Now we are dealing with aggressive fish here but sometimes it can be VERY tricky to determine if it's something to be a bit concerned about, something that needs to be dealt with immediately, breeding behavior or if it is normal cichlid aggression.
You are ALWAYS going to have a dominant cichlid in your tank. This is just part of cichlid behavior.
If you know the genders of your fish, interpreting their behavior is much easier. Male-male and female-female interactions are almost always unfriendly. Male-female interactions between two fish of the same species or two similar fish of the same genus are often flirtatious. Aggressive behavior also generally results in small injuries to the participants.
If a fish is constantly being attacked and desperately trying to get away bumping into decorations and out of breath it's time to call it quits and someone must be removed; either your dominant cichlid or the submissive cichlid being attacked. If they are not separated the dominant cichlid will kill the submissive one.
Below I have listed cichlid behavior so you are aware of what is going on and to make a decision if someone needs to be removed or if what you are seeing is 'normal' cichlid behavior;
Shimmying and Shaking
The fins and tail will look like it's vibrating and shaking. This is a sign of breeding behavior.
Flashing The fish will turn on their side and scrape against the gravel or objects. This is a sign of dominance or a sign of breeding behavior. The male will shake, shimmy and flash to get the females attention. However; you must note that flashing can also be a sign of illness.
Tail Wagging You will see the cichlids tail and fins wiggle like a puppy dog. This is a sign of dominance. This is just a normal part of aggression and all it really means is, "Get out of my way."
Hiding Your submissive cichlid may be hiding in a pot/decoration and too scared to come out due to aggression. They may not even come out to eat. At this point you should separate the two cichlids.
Lip-locking The two fish will look like they are kissing, but in fact they are displaying aggression and fighting for dominance or this may also be breeding behavior. You need to keep an eye on the two and if it still persists and if the two don't break up I recommend you separate them.
Flaring If you see the neck gills, flaring and the top fins sticking straight up this is a warning telling others to get out of the way. This is a normal part of cichlid aggression.
Circling Behavior The the male and female will literally circle around each other. It is really cool to see and once you see this you will automatically be able to tell they are breeding. The male may also circle around the females head and sort of flash, shake and wiggle his body. This can also be a struggle for dominance but usually it breaks off and things usually work out. However, I mostly see this when my cichlids are spawning.
Chasing Cichlids do chase and that is part of their trait but if they start biting, hurting and doing this constantly across the tank I would be concerned. There should be some kind of break from this and if it's just one chasing the other that is very stressful for the fish. If there is biting that is not a good sign. A few nips here is there isn't a big deal but when they are taking chucks out and missing scales it's time to separate. The submissive cichlid should not be chased around to the point that it is out of breath and weak.
Spawning Behavior Cichlids become extremely aggressive when spawning. You will notice they will start to dig and clean a spot and start re-arranging furniture in the tank for the eggs and start becoming extremely aggressive. If you just watch the behavior for a bit I'm sure you will be able to determine if they are breeding.
Signs of Cichlids Spawning; Shimmying or shaking
Lip-locking
Flashing
Circling behavior
If you are having a lot of problems with aggression & it's out of control & you don't know what to do, send me an Email & I will help as best as I can. I have been there & trust me, it's no fun!
Cichlids LOVE to dig so when you are adding decorations like rocks, always keep in mind that whenever you add is stable and will not come tumbling down on them.
Cichlids and most fish love and need hiding spots to feel secure. I would not recommend keeping live plants with cichlids as they will be torn apart and shredded in a matter of seconds. You can try plastic plants but they will be up-rooted because as we all know, they DIG DIG & DIG some more. What I find works is attaching some plants with an elastic band to a rock. I hide the elastic band with other rocks piled around it.
The way your tank is set up plays a huge role with keeping aggression levels down or increasing aggression levels. A bare tank with one cave and three cichlids is bound to reek havoc on how they behave. Or if you have three cichlids with no hiding spots this will stress them out and they will take it out on each other. If you have your tank cluttered with so much stuff they can't move is not such a good idea either.
I find a lot of rock work really helps keep aggression levels down. I leave a lot of open swimming space at the top. I find that having a lot of rock work helps different size fish fit in different spaces. I make sure all my little cichlids have a lot of little hiding spots and huts that the big cichlids can't get into.
Some way's to decorate to keep aggression levels to a minimum are, strawberry or clay pot's. They are cheep and work wonders. Each fish in the tank MUST have a territory; a pot, cave, tunnel, rock cave, something to call their own. I even just stick some floating plants in there to distract them. What I find my cichlids love is if I put big rocks in the back corners of my tanks and stack them next to each other and build a little fort. You can also use slate to build a little fort for them to hide under. Another good tip is some kind of decoration in the middle like a peace of bogwood to distract them. You can add a big peace of a wood decoration smack in the middle of your tank and this works wonders. When I raise my baby Red Devil fry and they start becoming juveniles I add NUMEROUS clay pots and hiding holes and this cuts down on aggression incredibly.
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