Poor Polyp extension on some SPS

[ratboy]

Im not the SPS-master that some otheres here are so maybe you can help w/ a problem Im having. A few weeks back my newly setup kalk reactor dosed while mixing for about 10 minutes and clouded my tank. Luckilly I was home and stopped the pump, reset my timers and did a 10 gal water change. The water quickly cleared and all my fish corals looked OK for the most part. My M digitatas stopped polyping up while my birdsnest and M caps still looked fine. I figured a pH spike or alk depletion was the cause but several weeks later they still look much the same. The crazy thing is their color looks better than normal (VHO/PC lighting) and I can see new growth on these and my other SPS's. Im going to do another water change tonite and see if that helps anymore but does anyone else have other ideas or suggestions? Is there a trace element I may have depleted that wouldnt be replaced fast enough w/ 10% water changes (Mg??).

thanks -Erik

[Goofball310]

Unfortunately you've run into a spot where many of reefers run into. I've run into this problem personally, and have asked numerous people how to remedy this. I've had frags go from my tank to other local reefers, with various results. Here are a couple of things that you might want to try:

Feeding your tank phyto
increase the current around that particular coral
some reefers have documented greater polyp extension after they have installed a refugium
check to see if the polyps come out when the lights are off


HTH