i feel refugiums cause more problems than they solve. i would just add a sump and call it good. actually i would add a settling tank and really make a nice system. most refugiums are just glorified settling tanks waiting to crash.
a refugium is only good at removing nutrients if something is removed from the refugium. you have to remove something in order to export it. this could be culling of algae, or the regular removal of the LR/sand in the refugium. both LR and sand act like phosphate sponges. they eventually will need to be exported or they start leaching phosphates back into the water column, eventually resulting in
algae blooms. depending on your feeding schedule this could become an every other year thing. of course if the SB/LR in the refugium are getting full than your display is also prolly getting full.
if you were to add a settling tank than all of the big detritus will congregate in a confinded area where a simple turn of a valve will remove most of the detritus from the system!! very little siphoning needed!
i just found a fairly inexpensive source for some smallish conic settling tanks and am seriously thinking of adding one/two to my system.
G~
