I have the same nem. It has been in my tank for 6 years. I was lucky when I started with it I was the person that liked the pinkish look to a tank so I had four 10k vho's. The nem anchored the first day by a rock through the dsb to the bottom of the tank. From research I have found that these like full spectrum light. And I have proven this theory. When I changed my bulbs the ran out of 10k so I got 12k along with actinics and the nem would not fully open I installed a 10k only one and over the nem and it's back to normal. They like to bury in the sand. Either sand only or against a rock they live along beaches in shallow water often 3 feet or less. They wash up on the beach for hours and float back out with the tide. I would do a 10 k light and give random water flow, not harsh sharp flow but a lot of gentle flow mine seems to like it when the short tentacles are randomly flushed. This will be a good starting point. Do not feed anything with bones or shells. I feed mine table shrimp, usually tiger shrimp. I also eat sushi and it gets the leftovers I have fed red snapper, tuna, salmon, it should be sticky to the touch but be gentle. My nems mouth doesn't gape but is visible when it's hungry. Feed about once a week something about the size of it's mouth but never feed it anything with bones or shells. There are many other things that are soft that u can feed it. Plus it's much cheaper remember the nem is very soft and it sucks ur tank water in to inflate.