Schools of Chromis

[nolofinwe]

I've been in the hobby for about 9 years now. In that time I've bought 3 "batches" of chromis.

I've had a 75 and now a 120, and every time I've done this it always plays out the same way:
Introduce ~10 fish.
Fish seem terriffic.
First night, ~1 fish die / go mia
Second night, ditto
This generally repeats until I'm left with five Chromis
From there I'll lose one more every week or two until down to 3.
A few months later I'm down to one.

Do they hate each others company? ***? It's a peaceful community tank. This time I introduced 12 into a 120 w/ 2 clownfish. I added 2 cleaner shrimp at the same time and they are doing great. But, every night there's one chromi that is hiding in the rocks while the rest are swimming around and looking great, and then in the morning: dead.

Does this happen to everyone else?

 

[zayn]

I have had similar experience with the chromis that I got about 1 week ago. I put in 11 and seems like I am down to 5-7 by today. Lets see what happens.

 

[nolofinwe]

Zayn - that is EXACTLY my situation right this moment. 12 went in the tank on march 5th, and I'm down to 6 right now - this seems to happen every time.

 

[zayn]

I was thinking that maybe the next time around, i'll add 2-3 and wait till they settle in and then add 2-3 again....

You know the funny thing is that I am having the same situation with Dispar Anthias...I added 12 about a 2 weeks ago and I am down to 5 now....I am not sure why...I have zero nitrates, .08 phosphates, ph 8.0, etc...

However, I did notice that the chromis pick at the small pellets but they love brine shrimp...any recommendations on feeding chromis?

 

[mingxu]

chromis

chromis

The same happended to me. I brought 3-4 to quantitine them, day by day died, I did serveral times, failed, only one survived. People says Chromis is hardy one, my experience is that it is worst in term of hardy. Any suggestions?
Ming

 

[reef_doug]

The best chance of keeping them is with a lot of flow. Tunze Streams + wavebox will help them school vs. hiding and becoming territorial. Also they are jumpers for sure.

 

[brookers]

i think they are quite hardy, they just pick on each other or the weakest, smallest one until it dies.

 

[5h3rW1N]

i think they are quite hardy, they just pick on each other or the weakest, smallest one until it dies.

+1 its true. they do better in odd number of fish the more the merryier lol:lmao:

 

[alcove]

ive always found that they find a weak one and buuly it or shun it from the school until it dies and then they pick the next weakest systematicly killing each other off, gotta love nature

 

[nolofinwe]

So how do you prevent that? larger schools? Bigger tanks?

It does seem that they all decide that one of them is not accepted, then that one dies. Then they repeat the process until there is one fish left.

 

[5h3rW1N]

just observe them at a LFS before buying them. I would ask if them can feed them to see how the chromis is reactiong to one another. and take a risk buy 5 or seven of the medium to large chromis's.

this seems to work for me. my parents have a tank just blue chromis's 60 gal FB hex with 15 of them swimming like lil guppies.

 

[jmaneyapanda]

Chromis are damsles, remember that. They will typically pick one another off constantly. I think a "key" to managing a group is to keep them under enough "stress stimulus", taht they worry about shoaling, rathering than beating each other up.

The whole odd number thing is a giant crock of you know what.

 

[nolofinwe]

I like that answer, Time to add that large angel I wanted.

 

[Beaun]

Chromis are damsles, remember that. They will typically pick one another off constantly. I think a "key" to managing a group is to keep them under enough "stress stimulus", taht they worry about shoaling, rathering than beating each other up.

The whole odd number thing is a giant crock of you know what.

+1 to this and I also believe that getting them as big as possible is helpful. Most of the ones you see at LFS are TINY. But keeping them stressed to be in a shoal is a key as well.

 

[nolofinwe]

Yea I dont think there's anything to the odd number thing - I seem to have an odd number every other day

 

[Wolverine]

Yea I dont think there's anything to the odd number thing - I seem to have an odd number every other day

I agree. The odd-number idea is a long held myth. If that were the case, if you bought an even set, as soon as one was killed, everything should stabilize, but that's not the case.

As mentioned above, they're damsels, and this is very, very common. IME, the tanks that successfully keep groups of them long term is in the minority.

 

[gatormoto]

i have two different tanks right now, both 120g. The first I put in 9 chromis 1.5 yrs ago, I now have 4 and that number has been stable for the last year. In the second I put in 7 and also now have 4, which has been stable for six months. On a positive note, my blue green chromis are laying eggs every 3 weeks. None have hatched so far (only have layed three times thus far)

 

[Lightsluvr]

Over the years, I've probably placed 30+ green chromis in my tanks. To this day, only one survives. As stated above they just bully the weakest of the bunch until only one is left. It's happened three times in three progressively larger tanks... Today, my lone surviving chromis thinks he's a dispar anthias and schools with that harem... go figure. :worried:

LL

 

[breakout]

I read in a Feb/Mar 2007 issue of Coral Magazine that it is imperative that a school of green chromis are fed several times a day. Their agression skyrockets when they perceive that they are in a condition of scarcity. You have to step up your feedings big time with finely chopped foods.

 

[lars on live]

I've had my school of blue green chromis for about 7 months now. I started out with 10. I lost one about 2 months in but haven't lost any more since. I have them in a 120 gallon. I feed them once or twice a day. They share the tank with a small coral beauty, a wrasse, and 2 tank breed Oc clowns.