Beginner with stressed fish problem

[owraight]

One of my blue-green chromis seems to have an ulcer on its side. Its left pectoral fin seems to keep 'sticking' to the ucler, which results in the fish flicking against the rock to free it. This in turn makes the problem worse, with the fin getting restuck within a few minutes.

I'm currently at a total loss as to what I should do about this, so am begging for any advice that I can get from you wonderful people :)

Here is the full version of my perilous quest in the search of aquatic harmony:

I am a total beginner at keeping marine fish but have kept freshwater fish for about two years, four years ago. Over the last month, I have introduced four blue-green chromis and two hawaiian chromis. About a week ago, my tank finished cycling (ammonia, nitrite and nitrate all now down to zero) and so I figured that it's time for the cleanup crew to get rid of all the algae. I have therefore added three blue legged hermits and ten snails (Astrae Coneheads? Possibly). They are making a good effort, but they've a long way to go. Shortly after they went in, one of my blue-green chromis developed an ulcer on it's side. I therefore hit the forum search and went out and purchased a quarantine tank. I put the poorly fish in along with some medicine; the fish was totally scared and immediately hid in the pipes I put in for it. After a day, it came out but was rapidly breathing (is that the right verb?). Another day and the poor thing was dead (yesterday). At the same time, another of the BG Chromis started developing an ulcer and that is where I am at now.

So, after all that, I am confused as to what I should do. Should I fish it out (pardon the pun) and transfer it to the QT, or just hope for the best? Is it an ulcer developed through stress or is there a parasite in the tank causing it to flick the rock ripping a side in itself? I added all of the livestock straight into the tank, only discovering the QT idea after the first one got ill: I'll be sure to use that in future though.

Here is a photo of the patient (http://s153.photobucket.com/albums/s204/owraight/?action=view&current=PoppyCloseup.jpg). The fish seems to be behaving completely normally, other than the flicking. It has no loss of appetite (as can be seen from the photo), although has suddenly become very scared of people getting close to the tank: the others are all fine.

So, if I haven't bored you to tears yet, any advice you can offer would be greatly appreciated.

Oliver

[serpentman]

Although you can never truly pinpoint the cause with 100% accuracy, the ulcer is likely due to a bacterial infection which was probably brought on by the stress of elevated ammonia levels from your cycle. The good news is if your levels are stable, its probably unlikely it will spread to other fish. However, this particular fish is in jeopardy.

At this point, you have 2 treatment options:

1. Do nothing. Keep your water parameters pristine and hope the fish's natural immunities catch up. Keep in mind, I am not familiar with your tank size. If the fish dies, it could raise ammonia levels if not removed.

2. Remove the fish to a QT tank and treat with a broad spectrum antibiotic.

[Icefire]

You cycled the tank with fish?

That might have stressed them...

What are your specs?

[owraight]

Sorry, I guess I missed out the important parts when writing the post.

I cycled the tank with just live rock in it along with adding some nitrifying bacteria to speed the process up. When all the levels showed zero, I then added the fish in pairs over the course of about ten days. I then let all the levels restabalised and added the cleaning crew.

Could it be the addition of all the snails and hermits that caused the stress? There hasn't been an increase in ammonia since I put them in (or atleast it's too subtle for the test I'm using), but could just the presence of so many scary looking creatures cause the problems?

The main reason that I'm worrying is that this is the second fish that has shown an ulcer about 36 hours after I removed the first. I built a trap (that I saw elsewhere on this forum) to remove it, but the fish was pretty wound up by being removed. It was rapidly gasping from the moment I removed it till its death. So I guess I'm pondering whether it would do more harm than good to remove the one that is currently ill.

During this last week or so, I've read a lot on the various medicines for fish, but in my LFS (actually my local street packed with LFS's), none have any medicine that states what it contains. Or am I missing something and that I should be going to the pharmacy and buying antibiotics from them? I'm living in Hong Kong at the moment and my Cantonese doesn't quite stretch as far as discussing aquatic illnesses (infact it barely stretches as far as ordering a beer), and the staff at the shops seem quite dismissive, so I'm quite reserved in trusting their remarks.

I'm more than prepared to move the fish to the QT, after all, it's just sitting in my bedroom empty being fed purely to keep the friendly bacteria happy.

My display tank is 105 gallons, with a 35 gallon sump. The temperature is pretty constant at 26C/79F, with NH3/NH4, NO2, NO3 and PO4 all at zero. The pH fluctuates between about 8.15 and 8.30 over the course of a day and the specific gravity is 1.0220. I have a protein skimmer (rated for a 200 gallon tank) and some other kind of filter (I'm not totally sure what this is, it was just something extra the LFS guys put on).

That's all the extra info I can think of for now, anything I've missed that might help, please do ask.

Thanks for all your help,

Oliver