Must you have a pre-filter box on skimmer ?

[potter]

Ok, I found a tang sucked up against our pump on skimmer last week and just thought it died and then got caught. Today I found our puffer half sucked up in the intake of the pump. Apparently, a pre-filter box is a requirement on a aqua remora? Or are the fish dying before the hit the pump? Thanks for the help.

 

[dogstar]

Those are not very strong pumps so, IDK, but all pumps that are inside a main tank should have sponges or guards so fish and anemones ect, dont get sucked into them.