Hey Ziggy, its coming along great. Getting delayed a little because I decided to go with another rimless 48 x 18 x 12 tank for the sump to match all of the tanks (for a nicer look). It also freed up about 350 gallons from my system because I'm not using that monster 400 gal Chem Vat for a rock sump anymore. After reading up a little more, I discovered that although the live rock does help nitrify waste in the system, there is very little needed because of the ULNS. So my system is the same display size but now only 600gal. That should save me a lot in dosing! Thanks for the interest!