something wrong in tank HELP!!!!!!!!

[bolt696]

My 55 gallon reef tank has been set up for 7 months now with no issues (that I know about). I recent have seen a big change. In my other post, I wrote about my koran angel, yellow tang, and damsels with faded coloring. My koran angel is now dead, and the damsels are breathing heavy. My tank (with a closer look), appears to now have black dots on him and he is rubbing up on the rocks. A closer look at some of the other fish makes me beleive they might have mild ich. My clown fish and anenomes appear to be doing fine as with the bandit shrimp and snails.
All the fish exept the clown are acting real wierd. They hang out together at the top ov the tank. They are all eating fine. I did a 25% water change yesterday, and the test this morning is as follows:
NH=0
KH=7 or 8
PH=7.7 (lowest it has been since I got the tank)
Salt=1.022
NO2= <.3
C02=5
I know something is wrong. I read most of the postings and I see talk about garlic????? I also read about some additives which some say work great, and some say it might have killed their fish.
As you know it is a lot of time an money put into this hobby and I would hate to have my tank crash. Please help:help: :help: :help:

 

[bolt696]

I also wanted to show a picture of something i noticed in certain areas of the gravel. I have these wierd things that look like works, but I have not seen them move. I guess i notices them a few weeks ago, but I thought it was waiste. It almost looks like they are sprouting out of the gravel. Are these parasites??? look close you will see it

 

[elfdoctors]

Black spots suggests black ich. The appearance is similar except the salt-grain-appearing spots are black. This is an entirely different different disease from regular ich. It is treated with formalin baths. This disease can be hard to see and is typically noticed on light colored fish first.
The worms in your substrate are actually a beneficial part of your cleaner crew. They probably hitchhiked in from the live rock.