I don't think it will stop, the smaller will be bullied until death by starvation or physical means.
I had 2 discus. 4 inch blue cobalt and a 6 inch Red Leopard. So today I bought a 2 1/2 inch blue diamond discus. And my Blue Cobalt has been chasing it around since I put it in, so I want to know if this aggression will stop. Also ever since I put the diamond in the tank, my red leopard has been acting weird. The leopard has been showing its black stripes, but it's always in the front of the tank with the cobalt. So does anyone know whats happening?
I don't think it will stop, the smaller will be bullied until death by starvation or physical means.
First of all it's the pecking order. Secondly three discus isn't a good number to start of with. The minimal number to start of with is 6 discus. Like Dennis said, it will bullied until death by starvation into physical means.
It's eating though.
Not trying to be unhelpful but I suggest you spend the next several hours reading beginners section. There are lots of things that you are doing wrong currently.
-john