You want to feed them some good quality food too, like Hikari gold pro, also you can give them prawns every now and then, or sinking shrimp pellets, these things help maintain a good red colours.
I had a little oscar in my tank recently but unfortunately he jumped, which is a shame cause I was looking forward to watching him grow. I know some day I´ll get another though, never too old or experienced to get another oscar!
beast mode