I'm not sure which genus the red and yellow neptheiids in the last two pics belong to. They might be easy enough to ID, just that I've never attempted it.
The red one was salvaged from a live rock bin, and the yellow one was an incidental attached to the rock of another coral I purchased.
I've seen brown, orange, and purple variations of the yellow one that were identical in all but colour, so it's possible there's wide colour variation in this species.
These two coral receive no special treatment. There hasn't been any noticable growth in the six or so months they've been with me. They're positioned them under a ledge near the front pane of glass, and receive reflected light from the glass and a solid linear water flow that cascades down the front pane and along the sandbed.
Both of these elicit a strong feeding response when diatoms are scraped from the tank's sides, which is about the only useful food they'd ever recieve other than detritus and whatever becomes liberated from the sandbed.
The system is fishless, skimmerless, and lucky to be fed once a week.
The red one's very tolerant of touching other coral and discosoma sp corallimorphs; it remains opened when rubbing up against all those I've positioned beside it.
That's about all the observations I can share in relation to these two coral.
On a different note, has anyone else noticed that with Nephthea species the longer the lights are on, the better they look? The ones I have take about 10 hours to expand to about 90% of their potential, and a full 13 hours to reach maximum. They're the slowest of any coral I've kept to rouse in the morning, they react quickly to the lights coming on, but take hours to look remotely 'awake'.