Hello all. Sorry in advance for the long post, but really need input. Been awhile since I've been on since I got my new aquarium...finally! I have had, what I've been told, the normal algae problems because I bought the tank from someone that already had it set up. The tank had been set up for about 7 years without major problems, per the previous owner. I'll start with what I have because I know that helps you guys, then I'll tell you kind of how it has gone, and what my problem is now.
Tank -- 125 gallon, ~ 150 lbs LR, several coral, 1 tomato clown, 1 maroon clown, 2 damsels, 1 neon dottyback, 1 snowflake eel, several snails, crabs, sump with wet/dry filter, protein skimmer, wavemaker with 2 power heads (1 is broke and hasn't been replaced yet). The lighting consists of 2 VHO bulbs, one white, one blue. The tank was moved about 3 weeks ago. I have kept up on cleaning filters, skimmer and feeding regularly.
About 1 1/2 weeks ago, the major algae problem (green and red) broke out and while it isn't getting any worse, it really isn't getting any better either. I added some carbon to the wet/dry, on advice of LFS, without any real change. I had to scrape the sides of the tank because you couln't hardly see anything it was so thick.
The maroon clown, who is quite a bit bigger than the tomato, is very aggressive toward the tomato. We noticed little "nicks" to the tomato with even a piece of fin a little weird and I can only assume it is from fighting.
Other than that, everyone seems to get along OK, even with the eel. That changed today. After cleaning the skimmer, I have noticed something floating on the water only around the return from the sump. I don't even really know how to describe it other than like a "flaky" substance that does not seem to be hard or anything. It is hard to see from the top of the tank, but very easy to see from the side of the tank looking toward the top. I know that sounds weird, but I don't know how to better describe it. Also, the tomato has since been hanging around the top of the tank and swimming a little "off kilter". This is not normal for him and is even more confusing because he will also take off into the tank and swim around and act normal.
The only other thing that seems slightly off is that while some of my pulsing xenia's are fine, some seem "unhappy" or kind of sagging. The other corals seem to be fine.
I am pretty sure this calls for a quarantine tank for the tomato, but I haven't needed one till now since I haven't bought any new specimens for the tank. I don't really know what to put in it though, or how big a tank to use. There are so many opinions and configurations out there and I just want to get opinions from here.
Please keep in mind when you respond that while I am trying hard to learn, I am still pretty new to the hobby.