Blue Green Chromis Schools - Issues

[LouH]

Almost every book or on-line description of the Blue Green Chromis states that they are schooling fish, and that several to a dozen should be introduced to the tank at the same time, and supposedly they will get along. This has not been my experience. Twice now I've introduced 6 and 10 Chromis at different times, and in each case the school singled out the weakest one and harassed it until it died. Then the next weakest one befell the same fate, etc, etc, until only one fish survived. My tank measures 72"X18"X18" (117 gallons). What is the issue here? Are the publicatins wrong, or should I try it again with a diferent number of fish? This has been a very unfortunate experience, because they are great looking fish that stay swimming in the water column. I would really like to be successful in keeping a school. They're supposed to be easy to keep. I've never had an issue with any other kind of fish. BTW, this is a SPS reef tank I'm putting them into.

Any ideas/experies to share?

Lou

 

[carlosR]

I was worried too putting in 9 chromis, small ones. They have been fine so far, two weeks. I feed them a lot during the day. I read that frequent feedings help reduce the hierarchy squabbles. Also I have several fish in my tank and that may force them to stay together rather than fight amongst themselves. I agree a lovely fish especially when they get along.

 

[AfricaOffroad]

I have to say I dont understand the chromis horror stories.
I have 2 sets of 4 in my 2 tanks.
They are best of mates.
I'm yet to see one of them harrass another????

 

[Kahuna Tuna]

My experience with these fish is that on the several occasions I have tried larger groups I always end up with a happily mated pair and a trail of corpses. Once that pair forms those two fish are all but bulletproof, these are a very hardy fish once acclimated but I have also experienced significant losses with new fish. I dont think these fish ship well as a whole. I think that success with a group of these fish may depend a lot of tank size and tank mates, along with getting a healthy batch of fish, not sure what the magic formula is yet.

 

[xxtriggermanxx]

I posted in a thread a while back how my 7 were doing just fine at the one year mark. I assumed it was because i have a large enough tank (7' 265 gallon) Sad to say I am down to just 3 and as of today the third is looking like his time is about to end... I won't try a group of these again. if you want a large group of the same fish I suggest you go back to fresh water! sorry for the sarcasim

 

[romanr]

I have 6 that school nicely and have for a couple of months. I did start with 10 and got down to six within a couple of weeks. The 6 are holding nicely and I hope they stay that way. I think strong current and frequent feedings are helpful.

 

[LouH]

Sounds like my experiences aren't too different than a lot of yours. I guess I'll just enjoy my one remaining Chromis.

 

[geaux xman]

started with 7 in 2 separate tanks and now down to 1. i'm never going to try it again.

i've seen a few tanks with 6-8 2-3" size ones. i'm guessing they just restock after some of them die off?

 

[LouH]

Re: restocking

Re: restocking

I can see someone frequently restocking if there is a good LFS nearby. I don't have that luxury, and from an ethical standpoint I wouldn't do it anyway. I hear that Royal Grammas will school. Possibly that is an alternative.

 

[EnderG60]

Chromis dont really school much. I got 35 of them for my 300g, and Im down to 12 in 3 months. Those 12 have been doing well for the past 9 months though. I plan to add another 20 soon hopefully to get the group to 15-20 fish.

Usual rule of thumb on chromis is buy twice as many was you want. Also when smaller then 1.5" they are not very hardy and require LOTS of feeding much like anthias.

From what ive seen feeding less then twice a day leads to more aggression in the groups which is when they pick off the weakest one(ove and over).

Also they really do not school. Mine are kind of all over the place unless something scares them. Then the school real nice

Ive also tried groups of firefish(did groups of 4 twice) I now have 1. As well as royal gramma's(got 3 and they did just fine).

If you want a nice group of fish, go with anthias. Just make sure you get the male/female numbering right.

 

[Kahuna Tuna]

They dont usually swim in the water column but I think there are several species of cardinals that will school/shoal and make an amazing display. I really like the lepticanthus longfins and I think they are fairly hardy once you get them going. On the downside they are a lot more expensive than chromis. What other livestock do you keep?

 

[anbosu]

In nature they school, but our tanks are a different deal.

 

[jhentr]

My eight has been doing fine for 2 months so far. Only slight chasing as far as I can tell. I feed 4 times a day heavy with my Auto Feeder along with additional feedings when I get home. I also have larger fish and a six-line wrasse that keeps the shoal close together sometimes.

 

[pwfish]

I have had a school of 6 chromis for about a year, I have had no problems with them, they are growing nicely and stay in a school most of the time. They are in a 125 gal tank. I would not hesitate to buy another school in the future.

 

[therman]

Bringing up this thread again. I've had a group of 7 for close to 6 months now without any targeted aggression. It took me 15 in several stages to get those 7, but all the deaths were in the first week or so of additions. They are at least 3 different sizes which are slowly converging, but size-wise there is plenty of opportunity for small ones to be the targets of aggression. These fish are ridiculously cheap in the U.S., after being caught and shipped halfway around the world. They must not receive the best care compared to a fish that sells for 10-100 times the price, which I think is half the reason many people experience such high losses.

One thing that seems to help has been the addition of an azure damsel. This fish is the self appointed king of the chromis, and regularly keeps them either schooling or in their hidey holes/corals. Since this fish was added they really seem more concerned with him than with picking on each other. This is in a 36"x36"x18" ~100g tank.