Kaudern's Cardinal semi-aggression question.

[goncharkina]

Hi Reef Central, I am very new to this, hoping for some expert advice.
I have a 150 gallon system, it is FOWLR huge tank. When I started, I added two little kaudern's cardinals together. They came from the same store, were quarantined together for 21 day with no problems, added to the tank at the same time. For the first couple weeks they were best friends swimming around with other fish. Last night I noticed that one cardinal is chasing the other (smaller) cardinal, and does not allow him to leave the rockwork. There are no problems between them during feed time (both eat like crazy), but I am not sure what is the problem. The tank is huge for two little cardinals and two clowns, there is enough food, etc. Any suggestions? What should I do for them to get along the way it used to be? :hmm2:

 

[mbauma]

I have 5 in my 140 and they have been there for about 4 months and are doing ok. Once in a while, I will see one chase another for a few seconds, but it has never gone beyond that. I would just watch them and see if it gets worse.

Worst case, you may have to take 1 back to the store where you got them.

 

[eatbreakfast]

Has the aggression only been in the evening? If so you likely have a pr and the male was holding a brood in his mouth. The evening is when they release the young, and even though they are the parents, they may still hunt the young, a.d this aggression toward the partner is just instinct sensing a threat to the young. The behavior should subside after the young are released, although they may spawn and hold eggs/young every couple of weeks.

 

[goncharkina]

I am not sure if they are a pair, and I know they are not fully mature/adults yet. I only had them for about a month and all of the sudden, the big one is aggressive towards the small one. But, you are right, now when I think about it the aggression is only in the evening and the big one will chase the smaller one as soon as he get out of his hiding spot. Do you think it will get better?

 

[anbosu]

I think you probably have two males or two females. They tend to not like the same sex.

 

[Shanet]

+1.
I have a pair and an extra, they do the same at night.

 

[snorvich]

I have 5 in my 140 and they have been there for about 4 months and are doing ok. Once in a while, I will see one chase another for a few seconds, but it has never gone beyond that. I would just watch them and see if it gets worse.

Worst case, you may have to take 1 back to the store where you got them.

As they mature, five will become two. On rare occasions a second female will be allowed to coexist.

 

[o2manyfish]

I have 5 that have been together for years. There are several males and 1 is always holding babies. I have now added 4 more that were born in the say system and all 9 of them are getting along okay. They are spread all over the tank and a couple hang out in pairs.

Dave B

 

[snorvich]

I have 5 that have been together for years. There are several males and 1 is always holding babies. I have now added 4 more that were born in the say system and all 9 of them are getting along okay. They are spread all over the tank and a couple hang out in pairs.

Dave B

In your 400 gallon tank?

 

[o2manyfish]

Snorvich,

In the 400 gallon tank I had 6 juveniles that I raised to adult. The appeared to be 4 males and 2 female with the way they split up and the number of them that were holding babies. About 7-8 months ago 1 of the males died with no apparent sign. Perfect finnage, fat, eating, just keeled over.

A year ago when I had my tank crash I had another pair of Bangai in my outside rock sump. They had babies that they released when the tank crashed. 12 babies survived the crash and survived the 6 weeks after the crash of nasty parameters and water changes. Too change water in my 1100 gallon system I siphon water out of the rock sump and pour bags of salt and tap water into the rock sump to mix the salt.

5-6 months ago the babies went over the rock sump overflow and ended up in the filter sump. So I put 1 pair in my display tank and 1 pair I gave to the original owner of the outside pair of Bangai. When they did great I added a second pair of babies from the outside to the inside.

So now there are 9 Bangai in the 400g with no signs of aggression. I have 2 males constantly holding babies. And the 2 juveniles that went into the tank first are almost full grown.

Dave B

 

[snorvich]

Dave,

What is possible in a 400 gallon tank (I have two large tanks) may or may not work in a much smaller tank. That was my point; not providing an absolute answer but a relative answer.

 

[goncharkina]

Update

Update

Just wanted to post an update about my cardinals. Two of them are still fighting, but they are ok. It turned out that two of them were male, so I went to the LFS and bought a third cardinal, luckily it was a female. Now trio is doing fine and even though they have occasional "arguments" none of them is being a serious bully.