Cull runts now or later?

[two utes]

I didn't think that i would be posting a thread in this section for awhile yet, but here i am.

I have moved a group of 50 odd 1/2'' or so juvenile discus off their parents into a grow out tank, and notice straight away that there are 3 runts that are also swimming irregular and mainly in a vertical position.
I realize that they will have to be culled at some point but not sure when the best time to do this is. If i cull them now will that cause other fish to become runts? or is their condition determined from birth?

....so do i cull them now or leave them till a later time?

I'm new at this so any advise or suggestions would be greatly appreciated.

[Second Hand Pat]

Hi Joe, if they are not acting healthy cull them now.
Pat

[two utes]

Hi Joe, if they are not acting healthy cull them now.
Pat

Thanks Pat

[Fishquake]

They are belly sliders. Their Swim bladder did not inflate. Culls.