These do require alot of specialized knowledge and regular(more than once a day) feeding of special foods like phyto, rotifers, and such. A 5g would not support them. Check out the photo gorgonians, like this one
https://www.live-plants.com/purplefrilly.htm, there are others that are very nice. I can't find the pics of my pics of the photo gorg collection I had, but here is a nps that I had, just for your curiosity. It was an awesome build, but finding enough nps to support it was too frustrating, so I shut it down.
Well primarily I'm a predator guy, but I have always had a fascination for nps corals. Most of the equipment is recycled from previous tanks, and it is in my fish room. An outline of the build; it's a 40B with a 20L sump, will have a refrigerated food dosing system and an automated water...
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