water flow through equipment?

[CoralBeauties]

Well I have finally started to set up my sump room and my 180 gallon tank (aquavista's old tank).  I will be running my tank overflow first into a tub which will hold my skimmer.  From there I will route it into my 55 gallon sump/refuge then back to the tank.  My question is I will be running 2 deep sand bed buckets in line and also a calcium reactor and would like to know where everyone thought that I should get the supply water and where to return the water.  I have 2 maxi-jet 1200's that I will use as a supply pump.  Should I put the pumps in the skimmer tub or the sump?  How about the returns, back into the skimmer tub, the inlet or outlet of my sump?  Thanks for the advise.
Jeff