Aggression...

Sk8r

Staff member
RC Mod
...is a sign you have too many fish, too small a tank, or inappropriately mixed species.

Territory defense and chasing is business-as-usual for some species. If there is no injury to the intruder and the chase stops, no big deal. That's just chasing the neighbor lad off the lawn.

Pieces out of fins and wounds are another matter. This leads to dead fish, diseased fish, and a failing tank.

What's enough room? Size of the fish is NO indicator of how much room they need. If the swimming is easy and the fish reaches a turn-back on his own without running into something, he's at ease and has enough territory. If he runs into glass or gets chased off by a neighbor, that's to watch. You may just have overstocked. Fin-flicks, direction changes like a guy standing on a street corner and wondering which way to go, OR aggression, fin-display, nervous twitches, all are indication of a fish feeling confined. This can lead to a decline in health of the fish in question; and can also indicate your tank isn't producing enough oxygen --- which can kill everybody on a too-warm day (warm water loses its ability to 'carry' oxygen) ---

Certain species are perfectly fine until crowded. Clowns, other damsels (the clowns are damsels,) gobies, blennies, angels, tangs--especially; rabbitfish---all these are great mixed-tank fish, until you either put in a rival, or get too many fish in too little space. Then fish will mysteriously disappear, one by one, fins will get ripped, and it's just not fun.

Aggression is a panic reaction: it's fear, and discomfort, and it's going bad places. If you're seeing this in your tank, you've got a problem, and you need to thin the herd, check on tank size requirements, and make sure your rock arrangement has a sleeping hole for every fish.
 

Misled

RC Mod
Staff member
RC Mod
Agreed. IMO a lot comes from having the knowledge of the fish and it's habitats before purchasing them. My tank has four fish. Unless it's feeding time, you normally only see two, the pair of percs. They tend to hover around the leather they host at this time. They are four years old. The female rarely leaves the leather. The male does whatever he wants, but every few minutes, he'll stop by and visit the female. Sounds like us humans.

My two pajama cardinals normally only come out at feeding time. They spend most of the time in the caves that were set up for them when the tank's rockwork was designed. They'll come out if you walk over to the tank, but after you leave, they go back into the caves. They are four years old and have been in the tank with the clowns since the tank was set up.

I've never seen a fish chase or nip at another fish. Normally, the fish both stay in pairs. Once and awhile after feeding, they'll swim around, but after an hour or so, the cardinals are gone, and there's two clowns dancing and playing with each other.

If I had to, I'd describe my tank as peaceful. That about sums it up.
 

gone fishin

New member
Sk8R great post. I was just reading a thread about damsels in a 180 that you responded to. I believe I may add a damsel or two in the 180 I am filling up now. I only had experience with them in a 30 I started with a few years ago.
 

Sk8r

Staff member
RC Mod
A 180 will let you get some beautiful movement out of damsels. Their little chase behavior usually figure 8's back to home territory, and everybody does the loop until somebody else violates territory, and then it's another loop: tall rock spires really help define this pattern, and serve as a 'where am I' to bossy damsels. The overall movement is that beautiful 'schooling' behavior so often sought and so seldom gotten. Damsels are relatively cheap, hardy, and given enough room, they move fast enough to avoid the rowdier ones---I had a blue velvet that was fat as a salmon and objected to anybody crossing his (central to the tank) territory---but they were all fast, and he didn't really want to catch anyone. He never did, not in the years I had him before I had to sell the whole tank (crosscountry move.) Particularly pretty were the little flock of chromis, who schooled very nicely when the chase was on.
 

jamesbaur13

Apsiring Alhcohlolic
Agreed. IMO a lot comes from having the knowledge of the fish and it's habitats before purchasing them.

I agree for the most part, but our tanks are nothing like nature... you are better off with going with others experience with the said fish in captivity.
 

chrisfont23

Reef Monster
Damsels are super aggressive no matter where you are. My wife and I spent some time in Tahiti and they were chasing each other all over the lagoon. Having said I knew that, I have no idea why I have one in my tank.
 

Misled

RC Mod
Staff member
RC Mod
I agree for the most part, but our tanks are nothing like nature... you are better off with going with others experience with the said fish in captivity.

I disagree with some of that. While you may not be able to duplicate the habitat the fish have in nature, knowing their traits gives you vital information on they react with their surroundings. Sure, you can read about successes others have had, that goes without saying, but providing as much of a natural setting as possible is key for someone that wants to breed a specific fish. I also believe our tanks can be alot like nature. My tank as it sits now is over 5 years old. It was set up for what's in it. I haven't added anything in a couple years now. All fish are over four years old and are in excellent health. My leathers breed regularly and I remove them and give them away. It's pretty amazing what happens when you just stop adding new corals and fish to a tank.
 

chrisfont23

Reef Monster
I disagree with some of that. While you may not be able to duplicate the habitat the fish have in nature, knowing their traits gives you vital information on they react with their surroundings. Sure, you can read about successes others have had, that goes without saying, but providing as much of a natural setting as possible is key for someone that wants to breed a specific fish. I also believe our tanks can be alot like nature. My tank as it sits now is over 5 years old. It was set up for what's in it. I haven't added anything in a couple years now. All fish are over four years old and are in excellent health. My leathers breed regularly and I remove them and give them away. It's pretty amazing what happens when you just stop adding new corals and fish to a tank.

True dat. My tetra FW cardinal shoal do much better as a group than as one, especially with a bigger fish in the tank.
 

jamesbaur13

Apsiring Alhcohlolic
I disagree with some of that. While you may not be able to duplicate the habitat the fish have in nature, knowing their traits gives you vital information on they react with their surroundings. Sure, you can read about successes others have had, that goes without saying, but providing as much of a natural setting as possible is key for someone that wants to breed a specific fish. I also believe our tanks can be alot like nature. My tank as it sits now is over 5 years old. It was set up for what's in it. I haven't added anything in a couple years now. All fish are over four years old and are in excellent health. My leathers breed regularly and I remove them and give them away. It's pretty amazing what happens when you just stop adding new corals and fish to a tank.

For breeding, I would agree.

However, most hobbyists aren't interested in breeding, they are interested in wild colors/behaviors that make their tank aesthetically appealing.

I'm not saying you are wrong in your thinking at all... you are very right, more than most. All that I am saying is the typical hobbyist vs yourself differ in views.

So, nature tends to take a back seat...

As reefers we still do pay attention to nature (I'd love to keep a parrotfish), but nature is not the ultimate decision in our purchases. We ask others "can I keep ? with ?". Rarely is a response how one acts with another in nature... sometimes the species come from opposite ends of the planet, rather it is, "well I had ? and ?... they seemed to be good buddies".

Let's come to a real truth, as far as re-enactments are concerned most reefers grade a C+ on a good day.
 
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Sk8r

Staff member
RC Mod
I've heard tales from divers being pursued by the larger-species triggers. There is a fish who, unlike the damsels, is not bluffing.

Of course, there WERE my pair of clarkii clowns (a form of damsel, never forget), who went to a breeder because I was tired to being bitten bloody every time I had to adjust something in the tank. So yes, nesting damsels are nippy. I think that pair birthed every clarkii sold in Oklahoma for some time.

I would say that trying to keep any of the larger species runs bang up against the limits of the typical large tank... Tangs, for instance, have a breeding behavior that requires height as well as length of run. I've no idea what big angels do. So for some sorts of reefing, you're definitely not going to supply a large enough territory for natural behavior. You do have a chance of giving adequate space to, say, a highfin redstripe goby pair in a 54 gallon tank, because their behaviors and space demands just do not exceed about a foot in any direction. OTOH, the yellow watchman goby, about twice that size, is always on the move, and is always rearranging his space, which seems to run about two feet. WHether the yellows actually move along the reef periodically I have no information. But at least the 54 gallon seems to satisfy their typical range. But those are only 2" fish. Most damsels I've observed within a hundred gallon tank want about a 2 foot radius inviolate, and will chase for about five feet, counting a turn back to starting point...this is, however, only within the limits of my hundred gallon tank, so I can't speak to that. The problem of somebody trying to keep one in a 30 gallon tank---is, however, pretty obvious: that fish is going to be in a state of constant upset, just from normal going and coming. The owner will complain the damsel aggresses. The damsel is being driven nuts.
One of my favorite reef webcams is down: they had camera on a reef face. I watched this thing off and on, for long periods of time, and it was a great view of behaviors: the damsels and small angels sticking kind of close to one particular rock, and then the tangs and jacks and such come sweeping in from far vistas, to blaze through at fair speed; and the silly pipefish type that seems to swim up in the morning and down toward evening, and the squirrelfish that darts out now and again to have a look at the camera. It's a great little timewaster, but you can see natural behavior only rarely interrupted by human divers, such as those of us who don't dive can't normally see. I've tried to find a replacement, but so far no joy...I miss the thing.
 
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Paul B

Premium Member
is a sign you have too many fish, too small a tank, or inappropriately mixed species.

And sex. With damsels that is a problem because even if you are not interested in breeding fish, if they are in excellent condition, the fish want to breed and when they are old enough and in good enough condition that is about all they want to do, unfortunately with damsels, they have an annoying ability to change sex. (like some rock stars)
These fireclowns have been doing this for many years, the larger one is 18.
They can get along fine for a couple of years and even spawn, then for a year or two they will both build nests and fight (also like married rock stars)
Then for a few years, they will be the picture of a perfect marriage and spawn.
(Gives me a headache)
IMG_1769.jpg


As for cardinals, they do get along better in groups like these near the bottom of the picture

IMG_2146.jpg
 

Misled

RC Mod
Staff member
RC Mod
So I need to explain some of why I set mine up like I did. First, here's a full tank shot.

DSC_5325.jpg


This tank was set up to be long term, little maintenance. I've done sps, chalices, and other fads that go through this hobby. Heck, like Paul, I've been at this over 25 years. Now there are still a chalice and an sps or two still in the tank, but as some of these things grow in a well maintained environment, the tank becomes a fragging station. Don't get me wrong, I understand people wanting tanks like this, I did. After moving the creatures from my old tank into what you see now, my thoughts started to change.

I had 5 pj cardinals and started paying attention to their behavior. I noticed two were always together, and they would not allow the others to move about the tank. From what I had found reading about them, the caves were set up to mimic their environment in the wild. I know they live and breed in roots of mangroves, but that wasn't feasible, so caverns were made to give them places to hide. I couldn't find info on telling the difference in sex, so that took some doing. After working with a few of the big names in the hobby we kind of figured it out.

My Male.

DSC_5863-copy.jpg


My Female.

DSC_5863.jpg


The reason they were keeping the other three in hiding was because the other three were females. At an age of about three years, they were reaching maturity. The three were removed and given to others. Since then they have lived peacefully together.

I know, I'm rambling again, but I think this is a very good discussion. I have a few opinions on why in the ballpark ten year area, (alot others before), reefers start to have problems and their tanks start to go down hill. Paul has hit on a few, but for now, I'll keep some of mine to myself.
 

Sk8r

Staff member
RC Mod
It is a good exchange. This is why I would say with the more aggressive damsels, one of a species per tank: the only one I've ever had multiples of is the little chromis, who are pretty nonviolent except toward each other, if crowded. If you have only one you don't get the mating behavior. Enforced birth control.
Two clowns can tag-team a fish that's bothering them, and that's setting up a problem.
The worst clowns are the red types, which I have known (tomato) to grab another fish and feed it to their nem.

One of a kind prevents problems. FIsh don't 'need' 'friends' for complex social reasons. They want territory. They want to be king in their little square of tank. That's a happy fish.

I have only one pair of anything in my tank, two yellow watchmen, but when you keep a pair, they both go camo: seems the male only colors up yellow when he's advertising for a mate. Ah, well, at least they're cute.
 
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Paul B

Premium Member
Two clowns can tag-team a fish that's bothering them, and that's setting up a problem.
The worst clowns are the red types, which I have known (tomato) to grab another fish and feed it to their nem.

This is true, and my pair of fireclowns don't have a Nem, they have a bottle. But it is also red. Maybe red gets them mad. :smokin:

TankDec42011004.jpg
 
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