Success with schools of chromis

[jnarowe]

mine schooled for several months, particularly just before bedtime. They would get into a tight formation as the lights started to go out. Now it's every fish for himself.

[clsanchez77]

Hey guys, thanks for keeping this thread valuable

I have been watching this thread because I setup a 90g Gulf/Caribbean tank. My intent is to stock with multiples of the same animals to look a little more natural. The tank currently has 11 frags from the same Pacific Montastrea head, two other Montastrea heads and I am getting ready to add about 25-30 small atlantic Zoanthid colonies, again limiting to about 3 species (or as best as possible).

My plans regarding fish were two: a group of damsels and a group of gobies.

For the damsels, I am planning to add 9 Atlantic Blue Reef Chromis. So far I have purchased 3 direct from a diver. These for whatever reason do not do well in traditional shipping routes (diver to distributer to LFS to hobbyist). However after a week they are doing great. I know that does not say much but I am confident they acclimated. The diver also threw in a Sunshine Chromis additional.

Currently, I feed the tank three times a day, morning feeding is just phyto, so they don't care. Second feeding is around 6pm and is 1 cube of frozen brine shrimp. Final feeding is at 10pm and is a mix of phyto, oyster eggs and frozen cyclops, plankton and mysis.

I have a automatic feeder that I will be adding to the system as soon as it ships. I will then be adding 3 additional feedings a day (the smallest feeding possible) of flake and/or freeze dried foods. I also will start soaking the frozen foods in garlic and adding spirulina to the mix.

The tank has been setup for 15 months with no fish and I have worked up the feedings to 3 cubes a day with DT's phyto and Oyster Eggs twice a day, all with no fish in the tank. The tank is full of planktonic life and algae remains under control, but does seem to wane and wax. Parameter remain stable, not at Acro tank specs, but reasonable. So this should be a good base for heavily feeding the tank.

Also, since I have the sunshine chromis, I will add two more of those so I will have 9 blue chromis and 3 sunshine chromis. Also a small group of neon gobies. The 90g is aquascaped to provide plenty of hiding spaces within the rockwork, so as they go to hide at night, they all have a place to call home so should not fight over this.

It is also my understanding that the Caribbean Chromis live a much shorter life, about 2 years (good thing they are cheap). Around this time they do pair off in the wild.

So I will be watching closely for territorial and feeding behavior. I will also update on population numbers. I am already noticing 1 getting bigger than the rest, but so far he is not chasing others away. If I do start noticing the chromis getting picked off, maybe I will experiment by removing the biggest one and see what happens to the rest of the group.

Chris

[Whisperer]

My 5 green chromis are still a team and going strong. I think the occasional chasing of the sergeant major makes them bond more.
Just an update.

[renogaw]

I have 3 in a 75, but only for about 3 months right now. One of them actually jumped out and i put it back in. My kole and coral beauty generally are swimming enough that the chromis stick together.

[john37]

i started w/4 fairly large ones, 1 year later i have 3. i think the one died cuz it was sick...didnt look like they were picking on him or anything.

but they dont school together.

[jnarowe]

I am down to 3 or 4. Tried a school of black mollies but they are getting picked off about one every 3 days.. I really like those blue reef chromis and have a buddy with some in his tank. I wish someone with true knowledge about chromis would chime in about their behavior in the wild.

The ones I have left are growing but not being very social with each other anymore. Maybe if I add a trigger they willl school again?

[Scottkelly911]

Originally posted by Gary Majchrzak
pic taken on a wild reef.
Note that although there a lot of Chromis in that picture, they aren't "schooling".

Actually if you look at the picture, you can tell they are "schooling". Although it's within the framework of the Acro's, it's still schooling behavior if you look at their formations as most of them are in sub-schools within the school. Notice there aren't any in the open water column and also they're aren't any swimming in front of the ridges of the acro shelf on the right side of the pic. That show's that while the school is huge and takes up a large space, they're still exhibiting schooling behavior. Granted because of the sheer numbers of them, some within the school will be a little more independant but it's still within the school.

Nobody's answered my question though, has anyone kept a small school of Blue Reef Chromis with a small school of Green Chromis? I am going to try it out as soon as my LFS gets some Blue Reef Chromis in stock.

[Gary Majchrzak]

Originally posted by Scottkelly911
Actually if you look at the picture, you can tell they are "schooling".

let's look at the picture


actually, it appears that an aggregation of Chromis are sheltering in a large coralhead.
It certainly helps if one defines the terms "schooling" and "shoaling":

A shoal is a loosely organised group where each fish swims and forages independently but is attracted to other members of the group and adjusts its behaviour, such as swimming speed, so that it remains close to the other members of the group. Schools of fish are much more tightly organised, synchronising their swimming so that all fish move at the same speed and in the same direction.

The Chromis in the picture above are definitely not schooling.

[reef3r]

It seems like success is most likely when there's 7+. Failure is most likely when there's more than 3, less than 7.

[jnarowe]

what Gary said!

[Bryan89]

Originally posted by Scottkelly911
Nobody's answered my question though, has anyone kept a small school of Blue Reef Chromis with a small school of Green Chromis? I am going to try it out as soon as my LFS gets some Blue Reef Chromis in stock.

I have 4 green chromis and 2 blue reef chromis. They all hang out together, but the blue reef chromis are MUCH larger as they were introduced about 4 months earlier. Everyone seems to get along, but I heavily feed also.

[Scottkelly911]

Originally posted by Gary Majchrzak
let's look at the picture


actually, it appears that an aggregation of Chromis are sheltering in a large coralhead.
It certainly helps if one defines the terms "schooling" and "shoaling":

A shoal is a loosely organised group where each fish swims and forages independently but is attracted to other members of the group and adjusts its behaviour, such as swimming speed, so that it remains close to the other members of the group. Schools of fish are much more tightly organised, synchronising their swimming so that all fish move at the same speed and in the same direction.

The Chromis in the picture above are definitely not schooling.

Gary, thanks for defining the difference between a Shoal and School. By those definitions, you are definitely right and it makes perfect sense

[checkinhawk]

ive got 4 in my 14g cube,they are going on a 2 months now and all doing fine.i plan on moving them to my 150 once its setup.

[kolokefalo]

I wonder if the aggression is caused by not having any natural predators. Also, it seems after reading this and other threads most of the aggression is caused upon reaching sexual maturity. I wis one of the big authors would do a study on the chromis in captivity.

[clsanchez77]

To add to kolokefalo, I also suspect under feeding causes the chromis to compete within the schoal for food. Chromis in the wild grow to about 4-5" on average. We generally pick them up as juveniles (about 1-2") so they we are picking them up with very large appetites. Then only feed the tank once a day on average to limit algae and nutrients.

Chris

[spaceyboy]

started with 10 I lost one in the first week, the rest are happy

[goldmaniac]

I had a school of 20 and they did great for about two and a half years. VERY slowly did one

eventually succumb from being picked on, and as the numbers slowly decreased, the decreasing sped up.

Eventually when I got down to about 10, they started getting knocked off pretty routinely, about one

every month or two.

here's a pic from WAY back when i started my tank, with the flash, it looks even worse than it really

did:







\not sure of my html skillz...

[jnarowe]

that is EXACTLY what has happened in my case, and now the ones left have gone to seperate areas and make virtually no contact with each other.

[mst3kguy07]

i did fine with 4 in my tank!

[Von_Rahvin]

with blue chromis in the wild they do school. but they are mid water fish. you usually find them 10' off of the bottom in a 60' water column. that's just how I see them when i dive. but they also are usually fairly large, 3-4"

[davocean]

I've had the same 6 chromis for 5 yrs now, no problem.
Mine have even adapted to go in and out of both my nems.

[jnarowe]

whoa, that's cool!

[davocean]

Yeah, I'll never forget the first time I saw them go in, certain any moment that a tentacle would touch them and ZAP, nem food!
But no, they swim right through tents no problem.
It actually caused a problem w/ a couple new fish I had, thinking they could go in as well.
I lost 2 young blond naso's that way.
One lasted 1 day, the other 2 days.
$89 each, expensive nem snacks!
Then I had to wake to seeing their bones spit out the next day!

[Gary Majchrzak]

factoid: the singular of Chromis is Chromis

[jnarowe]

The one I have left is hosting in a hydnophora.