So in the refugium what do you have? Other than chaeto? Did you put anything on the bottom? Also if you don’t mind can you please give me a picture of your sump? Along with the size? PleaseI think bio media would work. Not sure about sand as they tend to trap detritus.
I used to have a very healthy and robust pods population. However, most of them disappeared since I started using Fleece Roller about 5 months ago. I think the fleece rollers did too good of a job of filtering out the "foods" to sustain pods.