Is that inside the tank or the overflow box? My cichlids are thugs too!
@OP: When I read the thread title, I figured an emergency drain was going to be installed in your sump so as not to overflow if the power goes out or a pump dies, etc. I think I read this is your first sump so I would advise you to make sure that your sump does not overflow when the pump is off. It is a common beginer mistake and wet floors are a pain to deal with. GL with your project.
I was thinking the same thing, also if you space out when filling after a water change. This way your sump won't overflow
