also, a sump/refuge creates just as much nitrate as a cannister, the difference is that it creates a safe haven for the pods, and it gives you room to add things that help with the water chemistry like a deep sand bed for anaerobic bacteria to turn nitrite into nitrate.

Can I use a coil denitrator, instead of the deep sand bed?

As for the safe haven for the pods... i dont think i need one since my tank will be stocked with over 100 lbs of live rock and rubble, and my fish load will be very low (would rather have many, many, inverts and a couple of very beautiful fish).