Patience, that is the key word.
Fish are generally wary of anything new in their environment, some more wary than others.
In my case I needed to remove a Melanurus Wrasse from my tank. It had managed to eat its way though most of my snails, my hermit crabs, my pistol shrimp and two fire shrimp.
It was time to go!
I placed the open trap in the tank and watched all the fish avoid it for 3 days. I hadn’t placed any food in the trap during this period.
On the forth day the wrasse got nosy and entered it following some food which had inadvertently found its way inside.
It began doing this regularly after feeding.
I knew then when I would be able to nab it.
It is worth mentioning that only one other fish had entered the trap, most of the others were still very wary.