mudboots

IMHO - If they grew to 3 inches in a 20 gallon tank within that amount of time then that seems quite normal regarding nutrition availability (the butterfly fish I had for the time I had them were not shy about diving for shrimp when hungry, so the fact you are breeding shrimp is a hint). Most fish I've ever kept in aquariums of various sizes that were similar in size and agression seemed to reach a point where they simply wanted more personal space.

Again - IMHO - If each of your fish grew at the same rate then your feeding habits had nothing to do with it; they're just an agressive fish species.

Six

OK, well maybe they grow larger in unnatural environments like an aquarium where they get food all the time, but wild fish do not exceed 4-5" normally.

Fishyerik you may have 30 years of experience but you have 19 posts in this forum... why would anyone take your advice, especially since you're coming across rude? It's not even my thread and I felt as though you were being a little mean.

Just because fish are dying does not mean they are starving. Interspecific competition can be many things, competition for food being just one.
Aggressive feeding is hardly a way to tell if a fish is starved. These fish specifically are quick to jump at food because they are predators. Just because they jump at food and eat voraciously does not mean they are starved, especially this particular species.

fishyerik

Yes, kill the messenger!

What's the rude part?

I've not been very active here and not registered for a very long time, but my impression of this forum has been that most people who is asking questions want real true answers.

"Interspecific competition can be many things" you say, and yes, it can be about more things than just food, but all in all every reason boils down to very few reasons. But here was intraspecific aggression suspected, which reasons also can be boiled down to a few categories, where in the case of this species food is without doubt the most likely reason.

Yes 4 to near 5 inches is normal size for butterflyfish, not less then 3", don't forget store bought fish already has some size, 18 months is a long time for butterflyfish to grow to full, or very near full size from store bought size.

Aggressive feeding itself is not a sure sign of starved fish, I never wrote that, It's definitely not a sure sign of well fed fish either, or fish that has no problem with hunger, as Qwertus thought, that was what I was trying to explain.

And "Six", You also insinuate that my main clue to that they've been starved is the fact that they're dying, when it's very obvious that they still is/were so small is the main clue. If telling the truth is considered rude, and trying to change the impression of the meaning of what other people written is not, I don't mind being interpreted as rude.

Qwertus, as to the amount every fish should be fed it varies a lot, but 2 crickets each per day that are reasonably near the max size they comfortably can swallow should have grown them to around the 4" mark, if nothing else is wrong. 2 pinhead crickets a day probably won't keep a half grown butterfyfish alive very long.

The nutritional value of crickets can also vary, mostly with what they have been fed, gutloading the crickets with high protein, vitamin enriched foods might be a good idea. As is variety, there are other live and frozen foods they can eat and is good for them.

You can't compare the need for feeding between a highly specialized predatory vertebrate and a opportunistic scavenging invertebrate.

African butterflyfish are known for their ravenous appetites, it is very seldom bred, first reason is most people don't give them nearly enough food for getting them into spawning condition, so even spawning in aquarium isn't a very common occurrence, next problem is that the fry usually starves to death, not being fed enough of the right kinds of food. Starvation is a common reason for this species to die in aquarium, and it would highly likely be the most common reason if jumping out of the aquarium wouldn't kill so many of them before they had a chance to die from starvation.

fishyerik

Yes It is very common for starved fish to grow unevenly, if, they're fed as a group, and the strongest fish gets more food. Not so if they each gets about the same amount of food as it seems to be the case here from Qwertus's description.

In my opinion butterflyfishes would've become extinct a long time ago if their normal rate of growth were anywhere near less then an inch in 18 months when they pass half their normal size in year round tropical climate. Most small tropical species of fish usually don't live as much as 18 months in nature, How old would the 4-4½ inch individuals that's most often sold here have to be?

Most sources I've read state that butterflyfish are at the most slightly aggressive towards fish they can't eat.

I also think it's interesting that the shrimps are reproducing, but so were my cherry shrimp in my Belonesox tank, even thou I didn't feed the shrimp anything, and Belonesox is very much better adapted at catching shrimp between plants then butterflyfish are. And believe me, my Belonesoxes don't lack appetite.

I don't know if butterflyfish are sold at a much smaller size in the US then here, but I doubt it, correct me if I'm wrong. Here they are sold from 2 inches and up. If they grew from 2 inches or more to barely 3 inches in about 18 months, something has to be wrong, it's not a particularly slow growing species.

I've found that there's quite a few classic aquarium related problems I can avoid just by meeting the fishes nutritional needs, mostly in fish that are considered aggressive despite lacking any obvious evolutionary reasons to be overly aggressive I see a strong connection between level of aggression and feeding. For example if you keep a group of red tailed sharks together, and they terrorize other fish and are killing each other they most often calms down a lot if they get more food and stops being a real problem, even if they do "interact" with each other.

For a well functioning immune system food is very important, in a closed tank there might be no pathogens, but how many times haven't we heard about people who bought new fish and lost most or all old fish in the tank to some disease? Well I've heard about the phenomena countless times, and only had it happen too me one time, in over 30 years whereof most of the time I've kept between 10 and 20 aquariums, often trying new species, never quarantined.

Some of the considered hopelessly plant eating fish species aren't that bad if well fed, I've kept goldfish weighing over a pound i a planted tank with lots of different plant species including for instance, Cabomba and Myriophyllum without any problems, of course the goldfish grew fast, and had no heath problems whatsoever, and they spawned most days as long as I kept the plants from blocking out most of the light.

It usually takes surprisingly long time for fish to die from starvation, and they most often show signs of some other cause of death such as disease. Most people don't realize that well kept, including well fed fish seldom catch disease even with other sick fish in the tank, and that starvation often is the cause that the immune system failed.

There is downsides to feeding like I do, you have to have efficient filtration, and some fish do outgrow small tanks very fast.

And, not all fish species should be fed very much, Tropheus for instance, are "biologically programmed" to eat everything they can, and defend a feeding territory, no matter what the circumstances, because in nature they're grazers in a highly competitive environment and their digestive systems aren't built for large amounts of energy rich food, so you can't make them healthy docile fish by feeding them a lot.

Qwertus

If they are starving then they can just dive for the shrimps, they are very capable of doing so since sometimes shrimps swim up. They would kill AND eat the other butterfly not kill it and leave it floating there. If they wanted more food they would have just act agressively towards other fish until they run to ther other corner of the tank, they are too small to hog the entire surface of the tank. They act on instincts only, they don't have the IQ to think that if they kill the other fishes they would get more food, they would simlpy chase them away.

I don't care which species is it, as long as its 3-4 inches there is a limited amount of food it can eat daily.

Also, ALL the grow rate for fish curves. They dont grow from 3 to 4 inches in the same amount of time that it takes them to get from 2 to 3 inches or from when they were born to 1 inch. I'm pretty sure you understand that concept from your years of experience. There live span is around 5 yrs so the closer they get towards the end of their live time the slower their growth rate is, I'm pretty sure they stop growing at the 4 year mark.

fishyerik

Tell me, how could It eat another similar sized butterflyfish? they're not equipped to bite parts from other fish like piranhas or sharks, and they can't swallow it whole.

Relative growth rate potential is greatest when fish start to grow, and declines with time, absolute growth potential is greatest about half to 3/4 of normal max size, really near their normal max size growth slows considerably.

And considering your fish were about where fish has it's greatest absolute growth potential, it'd take them at least 5 years to reach sexual maturity if your's not stunted, and needing 10 to 20 times longer to reach sexual maturity compared to their comparable competitors would have rendered the flyfishes ancestors extinct a very short time after the first birds learned to catch fish.

Their instinct is to chase other fish away, about that you're correct. But in a limited space such as a tank, the chased fish can't flee, and the result is if it gets to far, death to the chased fish, it doesn't have go fast, until the end where the chased fish from stress, injuries and so on looses it's ability flee effectively and the keeper finds a shredded, what he/she think suddenly killed fish.

If your butterflyfishes could have caught the shrimps effectively enough to gain more energy then they would have to spend, believe me, they would have cleaned out the shrimp in almost no time.

Six

Quertus, you didn't starve your fish regardless of what is being said. Competition between fish may lead to one eating less food than another but for it to actually physically die from starvation is highly unlikely. Starvation is neglectful and though an overstocked tank could be regarded as neglectful, it wasn't neglectful feeding that caused death.
It is more likely that without as much food (this is not starving, this is just a result of less dominant fish getting less food)along with the stress of competition, the less dominant fish's immune system was more susceptible to disease or stress-related issues. The fish may have gotten less food, but it did not die from that. That is only a tiny fragment of what happened. Competition for space and competition for food are two different things.

That's all I'm saying on the issue. Regardless of how clear I am in my explanations I think I'll just keep getting bashed by the new guy. Useless to argue with someone who is intent on winning at all costs. I'd rather respectfully bow out.
Best of luck with the remaining fish.

fishyerik

I think you both been misinterpreting me, maybe it's because English isn't my native language, my goal is NOT to blame or put guilt on Quertus.

No one can be expected to do better then the very best he or she knows after a reasonably amount of research.

If it were live crickets I think it's very impressive to have the patience to fed them individually every morning and evening for 18 months, I can't recall even hearing about anyone fulfilling such a tedious task for so long "just for a few fishes".

Six, you call telling the truth bashing, I call it enlightening, maybe it's a cultural thing? You obviously don't know my intentions, and I have been patient with your little attacks on me.

In Sweden we have an expression, you probably have a similar expression, anyway, roughly translated it goes like this: It's better to look or feel like en idiot for the moment, then being one for the rest of the life.

I don't think Quertus looks like an idiot putting that amount of effort trying to make the life for the pet fishes as great as possible. It's just all too sad that not all advice are good advice.

I haven't bred butterflyfishes myself, so for you guys I checked in a book by a guy who has; "Breeding of aquarium fish" by Helmut Pinter, about one of the two pages he devotes to butterflyfish is about food, and he ends the description by clearly stating that it takes about a year for the fry to reach full size.

mudboots

Very interesting comment about English not being the native language (fishyerik) and that being a part of this issue. I have to admit that I felt that some of the comments were a bit rude myself, as if you were insisting that starvation and no other explanation was the result of Qwertus' fish demise. But taking into consideration the language usage and social differences I can see where there may have been some significant miscommunication.

Fishyerik - we do have a similar saying to , but ours may emphasize a key difference. The way you worded it, it seems to encourage speaking about that which you are knowledgable, where in our culture it emphasizes NOT speaking about that which one is NOT knowledgable (six one way, half-a-dozen the other). Our saying is "It is better to be thought a fool, than to open one's mouth and remove all doubt."

It's kind of funny, and my wife reminds me quite regularly. That said, I will follow Six in bowing out, as I am pretty confident that we have all given Qwertus plenty of information to start researching what is looking for. Qwertus, I hope you have not taken any offense to anything. One thing I'm slowly learning on APC is that we may not agree with everything, and some of it may not even be correct, but it ALWAYS leads us to learn more about the hobby we love, which leads to happy plants, happy fish, and a happy spouse (Melinda is NOT happy when the tank is not happy because she's the one who has to look at it all day).

Until next time, Stay out of the Mud (unless you have high boots!!!)

davemonkey

Qwertus, I hope you got the answer you wanted . Your fish didn't go hungry , they got territorial .