[JonezNReef]

Since you are using water from water changes wouldn't that water contain many of the nutrients that are in the DT. I think if you put some LR in a small sump ( i put mine on a egg crate shelf to keep in off the bottom of the sump to help avoid build up) that would give bacteria a place to live. I have always had fishless frag tanks when Ive had one up. My current frag tank is fishless but is tied into the same system as my DT.

I think with a small protein skimmer, a little LR, doser to keep ALK and Cal in check and good flow with water changes and it could be quite successful.