Tank Size and Cichlid Aggression

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ragin_cajun

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Sep 8, 2013
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I've been thinking about this alot. No better place than here to ask. Keeping Cichlids is all about managing aggression....in smaller tanks (125 Gal and less). But, how does that change with big tanks (96x36 and larger)? Do fish that will fight in a 125 stop fighting if put in a 500 gallon? Does growing up in a smaller tank make a fish more aggressive than it otherwise would be? Do Cichlids just want a territory of a certain size, and fight to keep others out of that space? Or will a 12 inch fish chase others all over a 10 foot tank just like they would in a 125 Gal? This is discussed all the time here in specific terms for specific situations (will fish X live with fish Y in my 125?), but I'd like to know how different this would be if I got a much larger tank--if at all.
 
Quick example. I have a 5 inch Synspilum, biggest in my tank, and it seems to defend itself if a Lyonsi or GT gets within 1-2 inches of it, and it'll chase them away for about 6 inches. I'm sure if I put a Jag in my tank, it'd chase any fish it saw within 2-3 feet, and it would chase the intruder back and forth across the tank for 10-20 seconds. Why? Does it just want no competitors within 3-4 feet? Or is the Jag just murderous and will attack the others anywhere in my 6 foot tank because it can? If I put all those fish in a 10 foot tank, would the Jag calm down and co-habitate? Could it be as simple as give these aggressive fish (Trimacs, Jags, RTMs, Dovii) a tank big enough that they can clear the 1,2,3, or 4 feet of territory that it wants to claim?
 
My opinon,,,is fish need there space inthe tank to feel safe ,sleep ,privacy or opposite . I raise my fish in 55 gallon first usually .5 to 1.5 inch size. Then throwm n 225 gal , i wait to there 2 to2.5 that way respect da big tank there new home, but introduced and growing up with each others help. especially when sexual maturity hits. Thats when i encountered more aggression or pairing or spawn attempts. But the older they get and live with each other they calm n become in a fish sense family. Now some wait until they get big enough to act belligerent umbee ,dovi there growth rate is long and they get big. I use big pvc pipes probably 10 to give safe havens for fish i always keep top 15 aggressive in the tank usually around 10 of them all different cichz never lost none to fighting 6 years. One thing too ,i only put fish that was with others in a community,never a fish that was raised solo.Solo fish are use to being king,hows that gone to stop just cause he or she was moved , can emotionally stress them the bickering not being used to it ,or other fish waste living breathing it not used to all combinations. If u were n a house 18 years from birth alone no tv.How would u react first time u got realllly mad ,instinct , first time attracted to opposite sex instinct ,to spawn or be dissed,anyway just risky solo fish over 5 inches. Good luck finding a answer
 
My opinon,,,is fish need there space inthe tank to feel safe ,sleep ,privacy or opposite . I raise my fish in 55 gallon first usually .5 to 1.5 inch size. Then throwm n 225 gal , i wait to there 2 to2.5 that way respect da big tank there new home, but introduced and growing up with each others help. especially when sexual maturity hits. Thats when i encountered more aggression or pairing or spawn attempts. But the older they get and live with each other they calm n become in a fish sense family. Now some wait until they get big enough to act belligerent umbee ,dovi there growth rate is long and they get big. I use big pvc pipes probably 10 to give safe havens for fish i always keep top 15 aggressive in the tank usually around 10 of them all different cichz never lost none to fighting 6 years. One thing too ,i only put fish that was with others in a community,never a fish that was raised solo.Solo fish are use to being king,hows that gone to stop just cause he or she was moved , can emotionally stress them the bickering not being used to it ,or other fish waste living breathing it not used to all combinations. If u were n a house 18 years from birth alone no tv.How would u react first time u got realllly mad ,instinct , first time attracted to opposite sex instinct ,to spawn or be dissed,anyway just risky solo fish over 5 inches. Good luck finding a answer

This just hurts my head.

To answer the original question, there's no definitive answer I'm afraid. It certainly can't hurt to have a bigger tank though. In the end it's down the nature of the individual fish.
 
In general, bigger tank = less aggression. How much bigger depends on the fish. Bigger tanks also allow for more spread out aggression as you can have more fish in there, which also leads to less fish deaths caused by aggression.
 
I've been thinking about this alot. No better place than here to ask. Keeping Cichlids is all about managing aggression....in smaller tanks (125 Gal and less). But, how does that change with big tanks (96x36 and larger)? Do fish that will fight in a 125 stop fighting if put in a 500 gallon? Does growing up in a smaller tank make a fish more aggressive than it otherwise would be? Do Cichlids just want a territory of a certain size, and fight to keep others out of that space? Or will a 12 inch fish chase others all over a 10 foot tank just like they would in a 125 Gal? This is discussed all the time here in specific terms for specific situations (will fish X live with fish Y in my 125?), but I'd like to know how different this would be if I got a much larger tank--if at all.
To answer your first question, in my opinion fish that fight in a 125 will still fight in a 500 gallon. The only difference is that in a bigger tank the less dominant fish will have more space to retreat from the dominant fish. This has the added benefit of usually meaning a lot less damage to the less dominant fish as the dominant may be reasonably satisfied with the retreat distance and therefore less likely to pursue as relentlessly as they would in a smaller space. How much room a cichlid feels he needs for their territory will be based on the individual the species their previous housing conditions and present housing conditions and therefor how big a tank will be needed to manage said aggression.

To answer your second question in my opinion what size tank(as long as it's reasonable for the fishes size at that time) the cichlid is grown out in plays little importance in their aggression as adults. The factors that I believe create a more aggressive fish as they grow is usually related to them being kept singly and territorial markers etc. Your cichlid is learning just as much as he's driven instinctually about territory how to define it's size as he grows. So part of how large a cichlid defines his territory is based on instinct as well as his experience in my opinion. So if a cichlid is kept singly in a 4 foot square tank as a 3 inch juvenile, then he'll learn to a degree to considers that amount of space a fair territory. Just realize as he grows his expectations of territory will be proportionately larger, this is more about his perception then anything else. At 3 inches, 4 feet squared for example was fair but at 6 inches he'll interpret that as too small because he doesn't realize he's gotten bigger he just realizes his territory seems to be smaller. So in order for him to perceive maintaining the same territory he'd have to be upgraded to a 8 foot squared tank.

Now if you add other fish to the mix after he's been kept singly and compound that with him growing and his territory naturally dwindling as he increases in size you can understand to a degree why aggression could become a problem. That's why it's always best in my opinion and a lot of others to buy juvenile cichlids in groups. The experience of being kept in a group will stifle to a degree their territorial instinct in many cichlids by influencing their perception of territory, essentially they adapt to a degree. Rather then being forced to adapt twice or three times or how ever many times someone changes their housing conditions by being kept differently at different stages of their life which obviously could cause confusion for them in the form of aggression.

I could go on but I'd rather not keep rattling on my opinion about every intricate dynamic as that could take awhile. I also want to point out of course there's always exceptions to the rule and of course some species adapt better to smaller territories and these methods then others in general so there are no definitive's. I just hope what I said above makes sense and helps answer your question.





My opinon,,,is fish need there space inthe tank to feel safe ,sleep ,privacy or opposite . I raise my fish in 55 gallon first usually .5 to 1.5 inch size. Then throwm n 225 gal , i wait to there 2 to2.5 that way respect da big tank there new home, but introduced and growing up with each others help. especially when sexual maturity hits. Thats when i encountered more aggression or pairing or spawn attempts. But the older they get and live with each other they calm n become in a fish sense family. Now some wait until they get big enough to act belligerent umbee ,dovi there growth rate is long and they get big. I use big pvc pipes probably 10 to give safe havens for fish i always keep top 15 aggressive in the tank usually around 10 of them all different cichz never lost none to fighting 6 years. One thing too ,i only put fish that was with others in a community,never a fish that was raised solo.Solo fish are use to being king,hows that gone to stop just cause he or she was moved , can emotionally stress them the bickering not being used to it ,or other fish waste living breathing it not used to all combinations. If u were n a house 18 years from birth alone no tv.How would u react first time u got realllly mad ,instinct , first time attracted to opposite sex instinct ,to spawn or be dissed,anyway just risky solo fish over 5 inches. Good luck finding a answer
That's a well thought out and detailed answer man.
 
Fish get along much better when they have more space. Even when I put the divider in my 600 gallon the fish get a bit testy. When its all open the do much better. I have many examples of this with my tanks.

Sent from the Monster Fish Keeping App
 
It's very obvious if you visit some public aquariums and see some huge tanks with tankbusters. You will be surprised to see home aquarium terrors turn into peaceful lambs in big tank. Here is a Midas tank in Shedd Aquarium Chicago. Can you see how peacefully coexisting the fish are, and there are no injury or split fins, even with pairs breeding in the same tank.

http://www.youtube.com/watch?v=RZ__0_X0v2o

[video=youtube;RZ__0_X0v2o]http://www.youtube.com/watch?feature=player_embedded&v=RZ__0_X0v2o[/video]
 
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