Aggressive clownfish

aglendinning

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Hi guys!

I’ve had my tank (a fluval evo 52L) up and going for about 4 months now with two just two clownfish in it with really no major issues up until now.

Last week I added a Yellow coral goby, which seems fairly settled, still shy but seems content.

Now however the larger of the two clownfish has started to become aggressive towards the other clown, to the point of damaging its fin. I’ve read lots about it could be a dominance thing, but just don’t want it to harm the other one. Neither of them seem to bother with the goby at all thankfully.

Anyone any ideas or suggestions and what I can do, or is it just a case of let nature run its course?
 

exnisstech

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Sounds like they're figuring out who is going to be female. Pretty much normal for clowns, especially when two young ones are added together. If they end up pairing chances are good you won't be able to keep other fish in a tank that size once they start spawning and protecting eggs.
 
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aglendinning

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Sounds like they're figuring out who is going to be female. Pretty much normal for clowns, especially when two young ones are added together. If they end up pairing chances are good you won't be able to keep other fish in a tank that size once they start spawning and protecting eggs.
Thanks for the reply! I may let nature take its course!
 

Tahoe61

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It is not nature taking it's course. You should put the aggressive clown in a breeder box and remove the bullied fish. Hard lesson learned, mature clown fish are territorial. In small systems bullied fish have no place to flee to. 🐚
 

Boosted2kSi

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If the aggressive clown is constantly pestering/attacking the other, they need to be separated unfortunately.
 

reefnoob9

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Thanks for the reply! I may let nature take its course!
3 Weeks after introducing a pair to my 32 G, today, out of nowhere, my smaller clown has died due to fin damage and possibly exhaustion.

I wish the fish keeping community had better integrity and transparency regarding clowns given that its a beginner fish for so many. I wish I had done more research. I wish from the bottom of my heart I didn't get a pair, and that some good samaritan had warned me.

So just saying, 'nature's could kill one of your clowns with the 'let nature take its course' approach.
 

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