Neons fighting

[bikeman]

I have a small tank with a variety of tetras (2 black neons, 2 tailight?, 4 neons and 1 odessa barb)

Two of the neons were added yesterday (making 4) and since then they'v ebeen constantly fighting. The fins on one look really tatty now.

This is the second time I have added neons and lost them because of fighting. I though they were supposed to be calm fish.

I have two questions:
i. Will the fins healup?
ii. Is the fighting because I have reached the limit of fish for my tank?

 

[Tokis-Phoenix]

Need some more info first
a. How many gallons does the tank they are in hold and how long has it been set up? Does it have a filter and do you use dechlorinator?

Tetras are shoaling fish and need at least 5 of their own species to shoal with and not a mixed group of tetra species, this is also the same for odessa barbs. All of your fish are peaceful fish although i am not sure by what you mean as tailight tetra(maybe glowlight you mean?) and they would be alot better off with more of their own kind.

Are you actually witnessing agression between the fish and full contact nipping/biting towards each other or just finding fins with tears and chunks taken out of them?
Neon tetras are not agressive fish although they feel insecure stressed when in too smaller groups and i suppose it is posible they would perhaps try to nip other fish in these conditions but a desease affecting the fins like finrot mistaken for bites in the fish's tails is more likely.


odessa barb profile;

http/www.thatpetplace.com/LiveFish/Produ...290/Detail.aspx

black neon tetra profile;

http/badmanstropicalfish.com/profiles/profile51.html

glowlight tetra profile;

http/badmanstropicalfish.com/profiles/profile62.html

 

[Lateral Line]

As TP has said, all of those fish are shoaling fish and should be kept in groups of their own kind, at least 5-6 fish. In smaller groups, atypical behaviour is seen which may include aggression which comes about by insecurity.

Whenever you add tetras to a tank which already contains that species, there will be some jousting to establish the new pecking order. This is normal, and usually does no harm. Again though, in such a small group, their could be enough aggression around to kill the weakest fish.

From our own Fish Index...

Black Neon

Glowlight

Neon

 

[bikeman]

Yes I realise that I have a bit of a mixed bag and that these would all be happier in larger shoals BUT that's just how it's worked out (they don't all survive).

The tank is well established and I do all the usual stuff so no problems there. All the existing fish have been happy and healthy for sometime.

That is until I tried to boost the neon tetra numbers. As I said before I had two and they were quite happy. Last month I tried to add 3 more and all three were beaten until they died (they ended up with no fins and could no longer swim).

Yesterday I add two neons and the same thing happens again. This is not fin rot - they were perfect when put in the tank and I can see that they are being attacked mercilessly by the two existing neons (the black neon, glowlights and barb seem as happy as ever). It seems strange that the neons were happier when there were only two of them.

It seems to be more than just establishing a pecking order and I wonder if they are actually stressed because there are too many fish in the tank (its only 25Litres). Mind you there were 100 odd in the shop's small tank and they weren't fighting.

 

[Lateral Line]

100's of fish in a dealers tank, i.e. vast overcrowding, also generates atypical behaviour.

In a really small tank, dominant fish are going to try to apply their dominance. In such a situation, it is no suprise that newcomers are harrassed to death.