building custom 400 gallon tank working on sump tank

[rudy1952]

question to experts ; i am building a 400 gallon tank with a custom sump tank seeking pictures for design. size of sump is 70 gallons with 1st dripping on bio balls to slow down bubbles flowing into c-skim 1800 chamber, overflowing into 2nd bio ball chamber overflowing into a refugium, overflowing into sand pit then out to pump. should i use some other media for additional filtration? open to suggustions
thanks
rudy

 

[brich999]

Look into my build thread for my setup, I didn't build it but I setup my sump and lights and stand