Serpae tetra problems, help please!

How aggressive can 3 serpae tetras get? The reason I'm asking is because since I got them on Friday, All they have done is nipped at the fins of my neons, Columbian shark, platys, and even my harlequins. Would the Serpaes be so aggressive if I got 3 more or would it still be the same? Should I move them over to the tank with my angel or would they nip the fins of my angel too? Please help. Thanks in advance.
Tom

 

Tom Serpaes are known to be very aggressive but less so in larger groups. BUT... both tanks are really overstocked and crowding can make most tetras aggressive so I wouldn't advise adding any more fish to either tank. Sorry. Maybe get another tank and spread some of them out then add to the group of Sepraes ?
Carol

 

Thanks.
Tom

 

Welcome

 

One quick question. Is it true that the more fish you have, the less chance they will grow to be full length as in the wild? Or is that just a myth?
Tom

 

To a certain extent that is true because they are stunted. This can cause internal stunting also.
Overcrowding usually causes ammonia, nitrite and nitrate spikes providing the perfect environment for diseases to grow and attack the resident fish. Extra water changes each week can help the chemical spikes to a certain degree but the over crowding will encourage aggressive behaviour because there isn't room to claim the territories the fsih need.
Carol

 

Interesting. Thanks.
Tom

 

Thought you would find this interesting .

Carol

 

Very interesting. I think you should put this in the freshwater beginner questions and have it at the top. Thanks.
Tom

 

Thank you for that suggestion I will present it to the other Mods.
Carol

 

Your welcome. More than myself are probably wondering the same thing.
Tom