Quote Originally Posted by IRescue452 View Post
If its acting what most people see as sick (fins clamped, tilted or sporatic swimming), its often just a toxin in the water like nitrites. No need to kill the fish before testing out easy treatments. It really just depends on the situation.
It's also a case by case situation, but medical treatment should be attempted before killing a fish, unless the illness/injury happened rapidly & the prognoses is low~non.

I have 20yrs of Fish experience so I'm fairly good at it (not a crazy pro, just good). I also know all my fish well & remember about 90% of the ones I have lost over the years.