Just a quick update: the nem has doubled in size, but it still doesn't like light and did not take kindly to the pvc connectors. It is currently eating a whole mysis shrimp every other day because it cannot photosynthesize. It is currently in a deli cup with a mesh lid in the overflow box of my waterbox cube 20. This allows me to easy feed it and keep it out of direct light while also protecting it from powerheads.
It still has no tentacles and no color. Does anyone have any suggestions to get it to regrow tentacles? I read a thread on here about giving a bleached nem a tentacle from a healthy nem to give it new zooxanthellae, but I don't think that will work until it has tentacles to photosynthesize with.