I do not run UV.
I run a little Carbon in a bag.
I am not running GFO in this system. I am considering, but for now I am letting my CUC and WC's see if they can handle any sprouts of algae - it is not out of control. When in doubt, hands out and keep up with WC's is my motto. I will only add GFO as a last resort. No need yet, no phosphates in the water column via testing.
You will start to notice extreme water clarity and you will <u>rarely</u> have to clean the glass when the pellets are established. It is amazing. Also, your polyp extension will be through the roof. In my first setup (nano cube), I noticed color improvement in several acro's very quickly. My current setup is a much less established tank and I have been fighting Bryopsis with Tech M, so the results were not quite as astounding as before. I look forward my my current setup to mature.
As with every system, they are unique and should be treated as such. Whatever you do, keep up with your WC's and your normal husbandry and maintain a high quality skimmer setup - skimming in very important in a bacteria driven system to remove excess bacteria and the nutrients they consume. A powerful skimmer will also help oxygenate the water, which is important.
Furthermore, I think that the more your system matures it may be beneficial to dose additional bacteria strains, but I would consider this rare and occasional. I think folks will get caught up in the "magic bottle" mindset and think they have to dose MB7 or Prodibio all the time and I have seen no need to do so in my system with any frequency....I just want to dose every few months to make sure there are competing strains of beneficial bacteria in the system.
I am not the expert, but hopefully this helps. I try to forget the pellets are there and run a tank as I normally would without.....