Closed clove polyps

[Ron Hammer]

I recently added a large clove polyp colony to my tank and it looked fine for a few weeks - nice purple polyps flowing in the currents etc. For the last few days however, all the polyps have remained closed (day & night). Not having owned these before, is this normal behavior? All other corals both softies and lps appear to be doing fine. :confused:

[EricHugo]

No, its not normal behavior. We'd need a lot more information to determine what might be going on.

[Ron Hammer]

About the only thing that has changed recently is I've been adding Kalkwasser via the top-off water. This has raised the ph to 8.3 and alk to 4.5 meq. Salinity at 1.025, temp at 80F. Light cycle 12 hours, actinic only hour before and hour after mains.
(4) 160w VHO's, 150 gal tank, evap approx 3 gals/day replaced by Kalkwasser. Frogspawn, Galaxy doing fine as are the softies.
I do have three cleaner shrimp which are quite active and I'm wondering if they may be running across the clove colony in search of food or something. Anything else you'd check?

[EricHugo]

Yes, the shrimp activity might do it. Anything else nearby? Use phosphate removers? What about nitrogen and phosphate levels?

[Ron Hammer]

No nothing else nearby within striking distance of sweepers etc. Nitrates have always been lower than I can measure. I haven't looked at Phosphates in a long time and but I use total algae filtration and I suspect that phosphates are being taken up by the algae. In addition, I suspect that any remaining will be precipitated out through the Kalk additions. If it were a more holistic problem, wouldn't all the corals be suffering? Or, are clove polyps more susceptable to some conditions than other corals?

[EricHugo]

No, all corals are not likely to be affected by the same thing. We have a danger by thinking of corals as a lump group. These are vastly different animals - different species, different genera, different families, different classes...we are talking about thing as different as kangaroos and birds - or more. Often, a chemical will greatly affect some species and others not at all - be it a metal, a toxin, or whatever. In your case, the trick is to determine what that is. I'd suggest water changes as a starting point and see if you get some recovery.