Fish fighting when I switched lights

[Nteal320]

I switched from my marineland led lights to a t5 fixture and all of a sudden the fish became more aggressive and are all fighting each other. They have all been raised together and have never had any problems before except every once in awhile one would chase the other around the tank for a second and then quit. But since I switched lights they are fighting and won't back down except for a minute here and there. I've been watching to make sure it doesn't get too bad but just curious why the light could cause this

 

[oscarchic11]

they prob look dif to eachother in the new lights. try switching the decor around, it should help.