How long do you wait after buying a fish?

[Porcupine Reefer]

Trick question, after I buy a new fish for an established tank which already has preexisting fish, how long should I wait before buying another fish?

 

[littlefoxx]

Trick question, after I buy a new fish for an established tank which already has preexisting fish, how long should I wait before buying another fish?

Up to you! If its established then you probably dont need to wait as long as a new tank! Also depends on your process (if you QT) or not

 

[raimundosantana]

If you are concerned with bioload, that will depends on your tank size and fish size.
You could add a fish a week if they are all small and the tank is reasonable sized.
I would wait one month if it was a tang in a 60 gallon for example.