# Why are they doing that!?



## bekki_s (Jun 20, 2010)

I recently bought some tetra's, danio's and harliquins, there were 12 in total. The fish i had in were 1 gurami, 1 angel, 2 clown loache's, 1 red tailed shark, 1 humbug catfish and 1 raphael catfish.
Everything was great for a few hours, then i noticed 1 of the tetra's had gone. 
I sat in the dark for 3 hours trying to work out what was going on, because bu the end of the night 3 had gone missing! 
But to my horror my catfish were behind it, my raphael which is only 2 inches was hurding them round the tank to my humbug and he was eating them!
I can' understand it, normally they have nothing to do with each other, and i've heard they are really peacefull commnity fish both of them. I just can't understand what triggered them to act like that!
They eat load's and have a varied diet.
I have since got rid of the smaller fish, because in 2 day's, they'd killed 4 of them. 
Am i wrong about them, are they not to be with smaller fish or any other fish for that matter??


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## hawksport (Dec 27, 2009)

Apart from the corydoras and suckermouth catfish there aren't many I would trust with fish that will fit in their mouths


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## Koira (Aug 11, 2010)

What size tank do you have? Any fish that will fit in another fish's mouth will end up getting eaten unless they have sufficient room. 

Remember, 1 gallon of water for each inch of fish, (and by this I mean each inch of each fish at it's maximum size). So do some homework on how large each fish species can get, how many of them you have, and add it all together. 

This will be the minimum number of gallons to keep them satisfied. If you want them to live together peacefully, add 50% of your total or just double the number. That way there's plenty of room for everybody. (;


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## Lawrence22 (Apr 14, 2010)

Koira said:


> Remember, 1 gallon of water for each inch of fish, (and by this I mean each inch of each fish at it's maximum size). So do some homework on how large each fish species can get, how many of them you have, and add it all together.


This rule really only works for fish about 2" in length. For example 6X2" platties do not equal 1X12" Oscar. The Oscar will have a much bigger bioload. Unfortunately most of the stocking calculators do not take into account the mass of the fish.


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## Lawrence22 (Apr 14, 2010)

This is the best stocking calculator I have seen, though I believe it is still in development. The author has researched a lot more than usual.
AqAdvisor - Intelligent Freshwater Tropical Fish Aquarium Stocking Calculator and Aquarium Tank/Filter Advisor


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## hawksport (Dec 27, 2009)

Koira said:


> What size tank do you have? Any fish that will fit in another fish's mouth will end up getting eaten unless they have sufficient room.
> 
> Remember, 1 gallon of water for each inch of fish, (and by this I mean each inch of each fish at it's maximum size). So do some homework on how large each fish species can get, how many of them you have, and add it all together.
> 
> This will be the minimum number of gallons to keep them satisfied. If you want them to live together peacefully, add 50% of your total or just double the number. That way there's plenty of room for everybody. (;





Lawrence22 said:


> This rule really only works for fish about 2" in length. For example 6X2" platties do not equal 1X12" Oscar. The Oscar will have a much bigger bioload. Unfortunately most of the stocking calculators do not take into account the mass of the fish.


Correct.

No matter how big a tank is sooner or later most catfish will eat any other fish they can fit in their mouths, a big tank will just delay the outcome


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## Koira (Aug 11, 2010)

Didn't actually read all the individual fish. The most common reason for


> _"really peacefull community fish"_


 is a cramped tank.

And I really just meant to encourage the tank keeper to research the various fish, what space they need, and offered a rule of thumb. You don't actually measure things with your thumbs, you get an idea of what size somebody is talking about and then use your brain and resources to define how big exactly.


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## Guest (Aug 12, 2010)

Koira said:


> And I really just meant to encourage the tank keeper to research the various fish, what space they need, and offered a rule of thumb. *You don't actually measure things with your thumbs*, you get an idea of what size somebody is talking about and then use your brain and resources to define how big exactly.


I think most us know what the phrase 'rule of thumb' means... :lol:

Also, not meaning to go off topic, which part of the states are you from? I'm from Oregon.


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## bekki_s (Jun 20, 2010)

> And I really just meant to encourage the tank keeper to research the various fish, what space they need, and offered a rule of thumb. You don't actually measure things with your thumbs, you get an idea of what size somebody is talking about and then use your brain and resources to define how big exactly


i have 9 fish in a 4 foot tank, so there is no way it's cramped...
He was in with small fish before and there was never a problem, but as soon as i got the tetra's he started eating them, didn't bother the danios or harliquins, just tetra's. He is as big as he will grow, the guy who i got him off had him for 5 years. 
And i researched every fish, and have read nothing about them attacking a specific species of fish, never mind working with another fish to get them.
He has planty of room and places to hide, he has everything he need's.


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## hawksport (Dec 27, 2009)

Your humbug isn't this humbug then?
Aquazoo - The Fish


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## bekki_s (Jun 20, 2010)

Yeah he is a humbug. But the tetra's were fully grown, and he struggled to get them in his mouth. 
The other fish were half the size and he didn't give them a second look. It was just the tetra's. 
That's what i was asking, why were they just attacking the tetra's.


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## hawksport (Dec 27, 2009)

No idea but he should grow to around 20cm


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## bekki_s (Jun 20, 2010)

He is around 3 inch at a guess. The guy before had him for 5 years and he didn't get him as a baby. How long do they take to grow? I've had him about a month


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## hawksport (Dec 27, 2009)

If he had been kept properly before you had him I would expect him to be close to that by now


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## bekki_s (Jun 20, 2010)

He was kept properly, the tank had just him in it, he was my gys pride and joy. And everything in the tank was got just for him. I can't understand why he's so small. 
Also can't seem to find mch on life span, some say upto 13 years, some say 4, and the book i have say's it's unknown!


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## Koira (Aug 11, 2010)

Chillinator said:


> I think most us know what the phrase 'rule of thumb' means... :lol:


Well, everybody was taking my rule of thumb as if I was suggesting exact measurements... 

Back on topic, you didn't mention tank size in the original post so I had no way of knowing. Seeing that they're in a spacious and good environment, and that he ate only the ones he could, I'd go with what others are saying, that he ate them because catfish eat whatever they can fit in their mouth. Good luck with them, in any case.


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## Guest (Aug 13, 2010)

I find it very unusual for Striped Raphael catfish (_Platydoras armatulus_) to consume other fish. I've owned several specimens over the years and kept them successfully with small characins with no obvious problems.

The normal lifespan varies, however these fish can live upto 15 years when well cared for.

What the OP has not provided us is a set of test results for pH, ammonia, nitrite and nitrate. Tank size is not the only factor that influences growth rates. Poor water quality can severely inhibit the growth of otherwise healthy fish and can be caused by more reasons than one, including inadequate filtration, an uncycled filter, inadequate maintenance and overfeeding.

It would also be useful if the OP could give us the exact dimensions of the tank. The aquarium may well be 4ft in length, however we do not know the width or depth of the tank. It is impossible to calculate water volume and draw a rough sketch of the stocking density with just one dimension.


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## Lawrence22 (Apr 14, 2010)

Chillinator said:


> It would also be useful if the OP could give us the exact dimensions of the tank. The aquarium may well be 4ft in length, however we do not know the width or depth of the tank. It is impossible to calculate water volume and draw a rough sketch of the stocking density with just one dimension.


On this point unless the OP's tank is a 4' cube or a 4'x2'x2' at least I wouldn't recommend keeping the Clown Loaches. They will eventually reach 12" and are better kept in groups of at least 3. Just my opinion.


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## Guest (Aug 13, 2010)

Lawrence22 said:


> On this point unless the OP's tank is a 4' cube or a 4'x2'x2' at least I wouldn't recommend keeping the Clown Loaches. They will eventually reach 12" and are better kept in groups of at least 3. Just my opinion.


That's a very good point. Emma Turner from loaches.com has some absolutely massive specimens easily exceeding 35cm/14".


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