Fish Aggression and Tank Size

[jlnguyen74]

Theres a ton of factors that lead to aggression. For 1, overstocking your tank like you did a few years ago is asking for trouble. Moving new fish to a tank that already has an established group of fish and the new fish getting beat up. Thats nothing new. The fish that have been in your tank have established the tank as their territory and will not be very accepting of intruders. As for when you moved the Arowana into a bigger tank, they fought because they were fighting for territory. I believe firmly that the bigger the tank, the lesser chance of aggression issues, but theres always exceptions to everything. When it all comes down to it, it really depends on the fish themselves whether or not they want to be friendly or kill their tank mates.

Perhaps, you need to read again. When I had them in the 500gal tank 2 years ago, I had hard time to introduce new fish. However, when I moved that same group to the 150gal tank last year, or into 300gal tank recently, I had no problem with introducing new fish.

 

[Water]

Perhaps, you need to read again. When I had them in the 500gal tank 2 years ago, I had hard time to introduce new fish. However, when I moved that same group to the 150gal tank last year, or into 300gal tank recently, I had no problem with introducing new fish.

Read my post again.

 

[DMD123]

Problems always seem to come when adding a new fish to an already established tank no matter the size. The process of raising the fish altogether from a small size does seem to help. Ive only had experience with my 120g and have really had no issue with adding new fish because they have always been smaller than my dominant Midas who has always had tankmates ranging from schools of silver dollers, pleco, other cichlids. When my midas gets into his new 210g home I will introduce a few other larger mild cichlids with him and see how things turn out. But even then I am not overcrowding or overstocking so I think it should work.

 

[jlnguyen74]

Read my post again.

I did, but I'm not sure if you read my post. Let me help you

I'm interesting in hearing other member's experience, prefer first hand experience, not second hand experience, or "google" information

I didn't see any experience from your post, besides your firmly belief, and your thought of my fish keeping practice

 

[Water]

I did, but I'm not sure if you read my post. Let me help you


I didn't see any experience from your post, besides your firmly belief, and your thought of my fish keeping practice

lol okay. I had Flowerhorn fry in a 10 gallon. Moved them to a 50 gallon tank and the aggression died down a lot. Thats what you wanted to hear? LOL

 

[kamikaziechameleon]

I haven't kept any "monster fish" but I did find that fish survivability rate from aggression goes up ten fold in larger aquariums. I think part of the phenominom you experience when moving down to smaller tanks is called overcrowding, its a tentative social dynamic that reduces short term aggression. I've never found overcrowding to be a long term solution. 2-3 years down the line the sub dominant fish eventually get killed or died of stress.

@jlnguyen74 I don't know enough about your setup but the kinda rule I go for is to realize the approximate area of the dominant fishes territory and keep it in a tank double that size. He will still be your dominant fish and he will own the whole tank but he won't fight for it, I find it shows the big fish is all piss and vinegar. Haven't kept p-bass but that is a large fish I'd assume a 600 gallon tank might be the size of a dominant fishes territory and as such you would have to go to 1,200 gallons to alleviate the issues you are encountering.

Just saying that I breed my cichlids in tanks that are more than double the recommended breeding size and the stress to females is far less with successful spawns and holding periods being maintained in the aquarium where as if I kept in the recommended tank size(and I have) one has to remove the females for the female to even survive let alone hold the full period.

When dealing with aggressive fishes I've found that introduction order, tank layout, diet, and tank size are the 4 variables that one must pay attention to. I would never intro a fish to a tank after putting my late Ctenochromis horei in He'd hunt and kill anything intro'd after him in any tank 6' or smaller That was one mean 6 inch fish.