[Reefland]

Good day all!

We picked up our first 2 SPS frags last week. I am not sure of exact species but...

One is brown and branching with lime green polyps. It is about 3" tall with several small branchs starting to sprig out.

The second is about 2.5-3" tall and green with brown polyps. Excellent coloration.

Both have been in our new system for a week and the polyps are not extending as they were in the store or even after the first night in our tank. The green one is slightly leaning so the underside of it does not receives light like the top side. On the underside, the polyp extension full but on the top side were it receives direct light, the polyp extension is not so great. Should I follow the obvious and move the frag to a lower light position or allow it to be and adjust?

The store had it under 12k and I have it under 10k DE (both 250w).

Thanks for any insight,
Scott Z.

[tendar]

My sps arcos do the same thing opening on the shaded side some and not at all on light side when the lights are on but at night after the lights go out the polys come in full bloom to feed.
Check them after the lights have been out for a while and the polys will be probably fully extend feeding in the water colum which is when corals mostly feed.
If it has been week I dont think I would worry about moving it they are just getting use to the new lights and system.

[kevinpo]

Scott,
IME SPS that have enough light will extend their polyps less than those in lower light. If you already have had them for a week I would leave them in the same spot for now. Check after the lights go out and see what kind of polyp extension you have then. SPS in the wild mostly extend their polyps at night due to fish picking at them. They will learn to extend during the day only if there are no picking fish or if the light level is too low to provide enough food.

Mine used to extend during the day and especially when I fed the fish but after adding a P. navarchus which is a nipper they extend much less during the day.

HTH,
Kevin

[MtnDewMan]

I too agree that in my experience, SPS will polyp extensively if they are requiring more nutrients .... With intense direct lighting, they may be getting the nutrients they need from the lighting and where the lighting is not as intense, the polyps extend to gain more nutrients directly from the water column. This is evident if you look in your tank after a couple of hours after lights out, you should see a hairy looking piece of coral with full polyp extension.

My tank is full of SPS and many coral do not exhibit polyp extension during the day due to the intense lighting I have. The coral out of direct lighting do extend their polyps more, however at night, all coral are fully extended.

[Reefland]

I wanted to give an update on these frags.

The brown guy must have been too close to the light; several of the small brnaches had the tissue burnt right off so I moved it down to the bottom of the tank. I am proud to say it appears to be making a nice recovery as the tissue is already starting to cover some of exposed areas and polyps are extending.

The green guy still has great coloration; in fact I think it may have become a bit darker green but the polyps only seem to extend late in the day (after the lights have been on for several hours). Their current placement seems to be fine.

Thanks,
Scott Z.