Help! I am going through the trials of a new tank, my first one. I have a 55 gallon tank w/ a 20 gallon sump/refugium. I have 75 lbs of live rock, a DSB in the refugium. 4 T5-HOs run 12 hours per day, and the light over the fuge runs 12 hours on a reverse schedule. Just yesterday, I started using RO/DI water (was using treated tap water, which resulted in a lot green hair algae). One yellow-tail damsel and one green clown goby have been there for just over two weeks. I have two new problems:

1) I put a chaeto ball in the fuge two weeks ago. The first week it looked fine. The second week, it disintigrated into nothing. The disintigration was accompanied by the green hair algae bloom in the DT. Also, there is not much water flow around the chaeto. Now, I'm noticing flat worms in the fuge.

2) Damsel has 2 white spots as of two days ago-- one on the dorsal fin and one on the tail fin. I thought it was ich, but now I believe it is not. The spots are too diffuse, and the fin appears to be eroding a bit. Looks more the photos I've seen of lympho. He is not scratching or breathing fast, but he hides more than usual. His color looks good. Does he need to be quarantined? (I have a QT). If so, for how long? Is there a way to be sure it is not ich? (I did read the wonderful sticky's about ich.)

Thanks!!