coral problems

Question
Hi, I have two questions. The first one is about my sun coral that I just got two days ago, it doesn't seem to want to open up and eat. I didn't accliminated at all-my fault. I've tried to blow some zooplankton to stimulate it and then try to feed it some BS. However, it looks really healthy, no tissue reciding, nothing. The tissue is plump. Any seggetions? My next question is about my frogspawn coral, it seems to be dying. It seems like the tissue is starting to recede. I checked all the water parameters and the only thing I found high was the salinity. Could this have something to do with it? I added some freshwater and now it's at 1.024-025 compared to the 1.030. I also read that overdosing on iodine could be a problem. I'm guilty on adding iodine supplement without testing for it. At this point i've cut on adding iodine. Have any ideas why my frogspawn might be suffering?
Thanx, Ricardo

Answer
Hi Ricardo. Frogspawn are very good water quality indicators. Though they can be quite hardy their failure to show good polyp expansion can indicate less then perfect water parameters. Iodine is a very cytotoxic( toxic to cells)substance. If you are not using a test kit to test for the iodine level in your tank then you should not be dosing your tank with iodine! Iodine is also a very misunderstood additive. It can actually cause rapid death in a lot of corals if added to a tank where it puts the level slightly above what is naturally found in seawater. It is even mentioned quite often as a necessity for keeping corals yet this may not even be true. If you are performing regular enough partial water changes then iodine supplementation is not needed and can actually be detrimental. All high quality brands of sea salt contain this trace mineral in just the right amount for any normal reef tank. By doing frequent partial water changes you are not just simply cleaning the waste products out of the tank you are also replenishing the nutrients used up by the inhabitants of your tank. There really is no substitution for regular and frequent partials. This could be the problem with both of your corals. There is also the fact that some corals can not be kept in the same tank together and the frogspawn are very sensitive to soft corals(especially those of the Sinularia species but others as well). Lighting, current and feeding are also major contributors to this corals health. The prefer bright yet indirect lighting, a soft but not too strong current and high quality meaty foods. They do not tolerate being walked on by hermit crabs and will often not open up for long periods causing it to miss out on the much needed light and over time slowly shrink away. You may have to experiment with placement of this coral as it does not seem to be getting everything it needs where it is.
Sun corals are very difficult to keep long term and should really only be kept by the most experienced and dedicated marine hobbyist. They are nocturnal feeders typically expanding their polyps at night when the plankton content on the reef is high. Unable to rely on the benefits of photosynthesis, these corals must be fed in captivity. Newly acquired colonies may need to be coaxed to feed by blowing food or brine shrimp juice across the closed up polyps several nights in a row. Within a few days the should open as the lights go off like a faithful pet waiting for dinner. They prefer dim lighting but can adjust to even the most brightly lit tanks. They also prefer a strong current. A lot of hobbyists who keep this coral keep it under overhangs or out of areas of bright light. This is not necessary and since these areas in a tank typically have a low current it is not advisable to do so. They are found in many places in nature from cave entrances to shallow water pools in direct sunlight but most importantly they are found where ever there is a high load of planktonic organisms for it to eat. You may have to just give it a few more days. Eventually if your water quality is good your sun coral should open up and respond to the feedings. This coral needs lots of food to survive and should never be left to go with out direct feeding any less than three times a week. More often is better but you have to be sure you have a very good protein skimmer to help keep your tank from getting overloaded with the nutrients from these frequent feedings.