Green chromis are murderous savages!

[acro-ed]

I think the whole "schooling/shoaling" thing is one of the biggest misconceptions in this hobby. It rarely, if ever, happens in a hobbyist's tank.
......
However, every time I see a stock list for a smallish tank that includes 3-7 chromis, I think, "That probably won't work like you hope it will."

I agree with this. I've tried having chromis in an assortment of 40g-120g tanks over the years and never had long term success.

I was right on the brink of making it work with the 150g and they did shoal together at times.

The behavior in the 300g is far more natural and seems like a major breakthrough. At times they will spread out in a line that spans the tank, and other times will come together in a tight ball. Sometimes they are totally independent, each minding their own business. But they go through phases throughout the day where their behavior alternates, but at least with this amount of space and hiding places I feel I am seeing "actual" schooling behavior....finally.

-Ed

 

[ca1ore]

I think the whole "schooling/shoaling" thing is one of the biggest misconceptions in this hobby. It rarely, if ever, happens in a hobbyist's tank..

Schooling certainly not; schoaling charitably maybe ... but probably not. You need size that most tanks never even approach and predators.

 

[TheKyle]

If your chromis are fairly new and dying you might want to check for symptoms of “Uromena Marinum”, or UM. This is very hard to treat and is usually a death sentence.

My experience was I bought 15 from one lfs in my area, they all died in qt from UM one by one as I tried to treat. It was really discouraging but I decided to try another lfs, got 16 and took a chance going straight into my 210g display. Have had them going on 8 months now with zero issues or deaths. Model citizens. Even the tiny runty one never gets picked on. I feed American reef hpd prepared mix once a day and auto feed pellets 4 times a day in addition. I also keep some anthias with them among other things.

 

[ca1ore]

Uronema can be a big problem with these fish, and once it's in your tank it's a devil to get out. Green chromis just aren't worth it in my opinion, but if you do get some, QT is an absolute must. It's not clear to me that all fish are suceptible to uronema. Anthais certainly are, but wrasses seem immune, as an example.

 

[nereefpat]

It seems like there is a correlation between active fish that live in groups and pick at each other (chromis and anthias) and UM.

 

[davocean]

Chromis and anthia are pretty similar in being prone to uronema, those most common I see posted.
Both are just dirty fish and need QT , I mean all fish should, but these are high up on problematic list.

I like the mix of chromis and anthia, they often are grouped together, and while it's a short run they do swim back and forth from one end to other in current of my vorts, good of a shoal as I'm gonna get!
I've always kept chromis in every tank I've had over the years, under good lighting and proper diet they are very vibrant, everyone has their own taste I understand.
Pics of mine swimming back and forth, no feeding time or anything.

 

[Walts O]

If you want schooling behavior I had a group of 40 rummy nose tetras in my discus tank and they schooled in formation an awesome sight

 

[eatbreakfast]

If you want schooling behavior I had a group of 40 rummy nose tetras in my discus tank and they schooled in formation an awesome sight

Unfortunately rummynose teras aren't reef compatible.

 

[Colin Fowler]

Who the hell decided that green chromis have peaceful temperaments? Every time I look away another chromis has been brutally killed by one of its own kind. My school of eleven is now a school of six. It’s only been a week or so. If you want a school of fish, go with anthias. Chromis are vicious killers.

I started with six, they killed each other till one was left, and it terrorized all the other tank inhabitants. Literally would go ballistic at feeding time and not let anyone else eat. Captured him with a fish trap and put him in sump gitmo until eventually he disappeared. Not sure what happened to that sob. Good riddence.

 

[Colin Fowler]

Who the hell decided that green chromis have peaceful temperaments? Every time I look away another chromis has been brutally killed by one of its own kind. My school of eleven is now a school of six. It’s only been a week or so. If you want a school of fish, go with anthias. Chromis are vicious killers.

Threadfin Cardinals are peacefull and they school. I have 4 and they are very cool.

 

[vetteguy53081]

I have a bi-color chromis. Total jerk and I cant catch him due to coral layout. Ive starved it since November and it cant be happier and is energetic???? Just my luck

 

[eatbreakfast]

I have a bi-color chromis. Total jerk and I cant catch him due to coral layout. Ive starved it since November and it cant be happier and is energetic???? Just my luck

Bi-color chromis behave exactly like a damsel. Yours is par for the course.

 

[PatW]

I had a trio of green chromis, Chromis viridis, and one murdered the other two while in quarantine. I just got a trio of blue chromis, Chromis cyanus, and they hang together and get along. The green chromis picks on them but since it is episodic and split between three, it has not been an issue.

 

[vetteguy53081]

Bi-color chromis behave exactly like a damsel. Yours is par for the course.

Perhaps not. Just got home from work and I should mention I added 7 damsels to the tank to give it a chance and it chased them all last night, so I turned off the lights. Upon viewing the tank, he killed them all. Yes, he is a sweet fish and worth keeping. I will take the tank apart tomorrow evening and eliminate this nightmare once and for all

 

[Grsfish]

I went from 5 down to 2 and it’s been that way for over a year

 

[DylanE]

I started with 6, went down to 4 over two months. Just added an awesome pintail wrasse and they decided to start going after him. They all took a trip back to the LFS.

 

[BantyRooster97]

I've had numerous and it always seems if there is one that is significantly smaller than the others, they kill it. Currently I have 4 that are about the same size & they are great together.

 

[Brooks Ross]

I’ve has a group of 5 in my 65gallon tank for almost 10months and haven’t had an issue at all

 

[Jesterrace]

Who the heck decided that green chromis have peaceful temperaments? Every time I look away another chromis has been brutally killed by one of its own kind. My school of eleven is now a school of six. It’s only been a week or so. If you want a school of fish, go with anthias. Chromis are vicious killers.

Yeah, I roll my eyes at any member of the Damsel family that people claim are peaceful. That's like the idiots who claim occ clownfish are peaceful. How many occ clown owners have been bitten? Mine was okay to me, but a complete jerk to it's tank mates and I believe contributed to the death of my scissortail dartfish.

 

[van7271]

Started with 7 about 5 years ago. They fought down to 2 in about a year then stayed stable at two to this day although they are constantly fighting with each other.