Hello im new to this site and was wondering if anyone could give me any help on building a29 gallon refugium for my 75 gallon reef tank.How many baffles do I need and how far apart should they be and would i need to step them down as I go or cut them all the same size.Also how do I figure out what size pump I wll need for a hang on overflow.One last question I want to do all the plumbing out of pvc is the pvc glue reef safe or do I need to get something special? Thank you in advance