Blue/purple Emperor Tetra

[alan3513]

Looking for a bit of advice. On Sunday i bought seven of what i was told were Emperor Tetras but on observing the fish and what i've gleaned from the internet they aren't. Emperor tetras (Nematobrycon palmeri) have no adipose fin but mine have. Mine seem to be (inpaichthys kerri) but depending on who's web page your on they are either Purple or Blue Emperors. Is this correct, are they the same fish and if so how do you sex them, thanks in advance of any advice, regards, Alan

 

[Colin_T]

emperor and kerri tetras are different fish. Emperors get bigger (longer & higher in the body). Male emperors have blue eyes and a filament in the middle of the tail. females have green eyes and no filament.
There are a couple of types/ species of emperor tetra.

Male Kerri tetras are more colourful than the females and they often set up little territories a couple of inches apart. They sit here and show off to each other and any passing females. They will also swim aorund in groups when not breeding.

 

[rocknurworld2006]

kerri males also have distinctive blue adipose fins which palmeri dont

 

[Polenth]

Is this correct, are they the same fish and if so how do you sex them

Male kerri tetra have a blue adipose fin and shine blue. Females have an orange/brown adipose fin and look more orangey in general.

 

[alan3513]

Is this correct, are they the same fish and if so how do you sex them

Male kerri tetra have a blue adipose fin and shine blue. Females have an orange/brown adipose fin and look more orangey in general.

Thanks, seems i have only one male as the rest of them have an orange adipose fin

 

[Rubyuk]

Hi guys

I'm planning on homing some Emperor tetras when my tank is cycled.

I know (or at least I've been told and read) that the Palmerir ones are hardy and quite ok for a community tank.

What about the blue/purple ones though (Kerris) Are they as hardy/peaceful.

Can the two species be mixed or is that a disaster waiting to happen?

Thanks in advance for any advice/insight

p.s I also saw some midnight emperor tetras in my LFS. Are they palmeri/Kerri or something all together different?

Again are they similar in terms of hardiness/socialabilty etc and could you even home say 5 of each in a big shoal of 15 or are you best just going for all one variety?

 

[alan3513]

Hi, Don't know about mixing the two or the midnight ones but my Kerris are very peaceful, they are with red phantoms, glowlights and some corys. They are great little fish, fast, use all levels of the tank and always come up to the surface when feeding.

 

[Rubyuk]

Hi, Don't know about mixing the two or the midnight ones but my Kerris are very peaceful, they are with red phantoms, glowlights and some corys. They are great little fish, fast, use all levels of the tank and always come up to the surface when feeding.

When you say fast Alan would you say boisterous (SP) or just playful as I know other posters have said the Kerris are/can be nippers?

 

[alan3513]

Hi rubyuk, Fast as in swimming around the tank, very active and seem happy using all levels of the tank. Don't bother any of the other species in the tank and never seen them fin nip. Great little fish. Think the Emperor tetras (Nematobrycon Palmeri) are more inclined to nip and are bigger than the Kerri, (only what i've read as never kept them). Alan

 

[Polenth]

I've never seen my kerris nip either. They're fine with other fish/snails.

They seem hardy to me. I didn't lose any when I introduced them. The only deaths have been age related.

The midnight ones could be the black version of palmeri. If you Google for 'black emperor tetra', you should find a few photos for comparison.