Like you I have 3 tiels also, they do fight every so often, but it hasn't gotten to the stage where they need to be seperated.
A reason why they could be fighting is jealously if one bird's getting more attention than the other(s).. could also be due to being overcrowded in their living space and they need more room.. reasons are pretty much endless. Anyways, they're like living creatures and aren't always going to get a long for various reasons and fights will/can occur. Usually there's nothing more than a lot of noise and the birds won't get phsically harmed, although if one of them does get harmed then you should seperate them into different cages.
A reason why they could be fighting is jealously if one bird's getting more attention than the other(s).. could also be due to being overcrowded in their living space and they need more room.. reasons are pretty much endless. Anyways, they're like living creatures and aren't always going to get a long for various reasons and fights will/can occur. Usually there's nothing more than a lot of noise and the birds won't get phsically harmed, although if one of them does get harmed then you should seperate them into different cages.
