Unhappy Coral plus Other Problems

Question
I'v been having trouble with my coral lately, most of them are closed or half close. Also, my candy cane coral (or trumpet coral) is slowly dying and possibly my passion tree coral is too. The only thing I can figure out that has changed in my tank is the nitrates are a little less than 20. I've been doing water changes to lower the nitrates, but the coral is still unhappy. I found a white gell-like blob on the base of my frogspawn coral and also found littler blobs of it on the bottom of my pump in my sump tank. Someone told me it was sponge maybe a year ago when I found it underneath one rock, but I'm still not convinced thats what it is. Also, I recently purchased a rose tip bulb anemone. During the first two, three weeks it was very happy, but now even the anemone is beginning to have half of it's tentacles shriveled or completely shrinking to a fourth of it's size. I feed the anemone, it has metal halide lighting, and it has a clownfish. One more thing I noticed was all the crabs in the tank seem lazy as of a week ago. They barely go anywhere or don't move from one spot for days, and most of them are all on one rock. The snails, shrimp, starfish, sea cucumber, and urchin all seem fine and actually move, just not the crabs. Any ideas?

Answer
it sounds like your tank is not completely cycled so it is entirely unsuitable for any type of animal. nitrites nitrates ammonia and phosphates should all be 0 in order to have a thriving tank. i would suggest having a friend or the lfs hole your livestock until the tank is in good enough order to put them back in. keep in mine passion tree corals are some of the hardest things to keep alive in the reefing hobby as well as anemones. they must have impeccable water conditions and must be target fed every other day or so.