# Boesemani rainbow responsible for killing smaller fish? Do they get aggressive when t



## Merriallynchian (Apr 25, 2017)

boesemani rainbow responsible for killing smaller fish? Do they get aggressive when they get larger? 

I have had a very peaceful aquarium for a while. 

Some of the small fish are ended up dead, one look like his face was bashed in the other one look like something tried to bit him in half


The largest 3 fish are a 

1. DOJO Loach(mostly look though gravel) 
2. Denison barb
3. Bosemani rainbow fish

The newest fish is the Bosemani rainbow fish which has been in for 8 months but only recently has become large. He is starting to look like a swimming pancake with that odd flat shape. 

Has anyone ever know one of these fish to try to eat or attack smaller fish? 

I have no observed any strange attacking first hand but I forgot to feed them one day and maybe they got hungry. 

Thanks.


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## OreoP (Aug 12, 2016)

I usually see them chasing each other but nothing as aggressive as what you are describing. @Greggz is the resident Rainbow guru.....he will have a better insight.


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## Seattle_Aquarist (Jun 15, 2008)

Hi @Merriallynchian,

I would be more inclined to suspect the Dojo loaches which are known to be aggressive toward smaller fishes. I've kept rainbowfish with much smaller species and had no issues.


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## iMacg3 (May 16, 2018)

None of my rainbows have actually killed any of my fish. Maybe chased them, but not killed them. They are usually peaceful fish. I would suspect the Dojo Loaches might be involved here....

What types of fish were found dead?
What size is your tank?
Do you have photos of the Boesemani?

You will need more rainbows if you plan to keep them, at least 3 - 5.


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## Merriallynchian (Apr 25, 2017)

iMacg3 said:


> None of my rainbows have actually killed any of my fish. Maybe chased them, but not killed them. They are usually peaceful fish. I would suspect the Dojo Loaches might be involved here....
> 
> What types of fish were found dead?
> What size is your tank?
> ...


55 gallon fish tank with plants and driftwood

White cloud mountain minnow ( look like something bashed its face) 
Zebra Longfin Danio ( look like something tried to break him in 2 like maybe either rammed him in the middle to grab him in the middle) 

This is a generic picture of what the fish look like. 

It has been in the tank for like 7 months and had that flat unique look from when I purchased him. So I am thinking its an adult. 










Thanks.


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## Greggz (May 19, 2008)

In general, Rainbow fish are peaceful and not aggressive. 

I keep a good number of large adult males, and I've added many small juvenile Rainbows over the years, which many times are only about an inch long. I also have some Oto's in the tank. I've never seen them attack or harass any of the little ones.

Rainbows in general have small mouths/throats compared to their body size. I could see them eating very small newly hatched fry, but anything over an inch and it's highly unlikely it's a Rainbow doing the damage.

Then again, anything's possible, I've just never experienced it in decades of keeping them.


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