Sump
 

Is there any real design you have to follow for building a sump or can you just use a fish tank or a big rubbermaid tote container from say Home Depot?

you can use any container, but you will likely want a baffle system to eliminate air bubbles from travelling back to the tank.

?
 

What do you mean "baffle system"?

Re: ?
 

Just a series of baffles in the sump that the water goes under and over to dissapate the bubbles.

Why are bubbles an issue? Just unsightly or some other problem :question:

Unsightly and reputed to bother coral polyps. They will also cause a greater amount of salt spray on the lighting.