possible body fungus

Question
QUESTION: Dear Karen,

I currently have a 20G tank with a clown pleco, a peppered cory, two dwarf
gouramis, and one (the partner just died) mickey mouse platy.  Most of the
fish appear to be healthy (the pleco seems permanently attached to one my
silk plants that it blends in well with and is letting algae take over my tank)
and no one is scraping up against the decorations and everyone (except the
pleco, which I never actually SEE eat) is eating well.  I've had my water tested
1-2 times a week at the LPS and they tell me that other than a slightly raised
Ammonia level (.5-1), the water is fine.  My problem is I've had a remarkably
hard time getting my tank population stable and now I think my platy has
case of body fungus.

Here is the history of my tank:
 I had just finished cycling my tank with 3 danios and had added (in order,
added every week) the 2 platys, the pleco, the catfish, and then 3 red
tailed/blue finned tetras (I don't know the name except they have the same
coloring as serpae tetra without all the flashy fins).  Suddenly, a couple of the
danios (which were recovering from an ammonia spike) started to hide and
not eat and then the all the tetras were dying as a result of having their tails
eaten off.  (I know the tails weren't eaten post mortem because I removed
them to a QT container as soon as I saw their tails were disappearing.
Unfortunately, it was too late and they eventually died).  

I thought that maybe the platys were getting aggressive since they certainly
"ruled" the tank. I know platys aren't supposed to be so aggressive, but I did
some research online and it said that some were inclined to nip at tails and
eat the slime coat off of other fish.  So I tried to take them back, but the LPS
wouldn't take them and suggested I get the gouramis to put the platys in
their place.  So I did and when I returned home with them, within a day one of
the platys starting acting sick, had a dulling white film over his spots and was
starting to "grow" the white stringy things on his underbelly.  The second
platy also has a dulling white film, but it's not as widespread and his behavior
is unaffected.  I looked on the my marcel diagnosis chart and it seemed the
body fungus was the most likely culprit so I treated the 20g tank with 5ml of
coppersafe and waited.  I also upped the temp to 80 degrees.  That was on
Saturday.

So today, the sickest platy died.  I removed the remaining healthy platy to a
1.6G aquarium so I could treat it with maracyn (I had to guesstimate the
dosage since one package treats 10G).  My question is, should I just go ahead
and treat the 20G tank with antibiotics, too?  I have to think that the whole
tank is infected, but so far, the gouramis are still shiny and colorful and the
catfish continues to root around for food, and the pleco continues to cling to
his silk plant.  I just don't want to throw off the whole tank by unecessarily
dosing it.  At the same time, I'm starting to feel like the grim reaper of fish.  
Also, shoudl I keep the temp high or does it not matter with the maracyn?  
My pleco is so in love with the plant, I hardly see him on the walls an

This is not my first tank, I managed to keep goldfish for a few years in my
1.6G.  I'm just not sure how common it is to have such a high death rate as
one sets up a tank.  Your advice would be greatly appreciated.

thanks,
ann

ANSWER: Hi Ann,
I think all that needs to be done is to let your tank finish cycling. The ammonia spike is definitely not good and probably causing a lot of fish stress and even the fungus developing.

The thing I'd do is-
*Get the ammonia levels down by changing up to 50% of the water everyday and using an ammonia neutralizer like AMQUEL+ or Prime water conditioner with your water changes. You may have to do water changes everyday until the bacteria are able to establish enough to take over and control the fish waste.

*Move any sick fish into a tank of their own to treat them. Instead of Mardel's medications I'd use Jungle Brand's Fungus Clear. I've never had this medication fail me before and it doesn't seem to put a lot of stress on the fish. During any fungus treatment this is what I do-

~Change 50% of the water everyday

~Redose the medication after the water change

While this is against the medication's instructions, it has never had any bad effects and seems to work best.

I hope this helps and best of luck!
Karen~

---------- FOLLOW-UP ----------

QUESTION: Thanks Karen,  

The ammonia spike happened because I went on my honeymoon and (naively)
used one of the 7-day feeding blocks.  The ammonia levels actually have
been pretty low and stable for the last few weeks and the people at the LPS
told me that the cycling was good.  Is that my biggest problem? Listening to
them?  Are there are any other sites or books you find particularly useful that
I could reference instead of whoever happens to be on shift at Petsmart?  

Anyway, I will definitely do the water changes.  But I wasn't sure if you
thought I should treat the fish that aren't exhibiting any symptoms, too.  
They are still in the main tank and as I mentioned, they must have already
been exposed to the bacteria that caused the body fungus on my platys.  I
didn't know if it was better to treat it now or wait until they actually develop
visible symptoms.  

Thanks again,
Ann

Answer
Hi Ann,
The best book I have found about aquarium fish is called
"The simple guide to Freshwater aquariums" It explains everything in an easier way and has simple guidelines. Definitely see if you can find that book. Maybe your local library will have it.

Listening to the people at most petstores (especially petsmart) is usually bad to do. They usually are very uneducated.

I wouldn't treat the fish that are showing no symptoms and are acting healthy. I would just treat those that show sickness. I know that when a disease happens to appear in your tank, it doesn't always mean all the fish are going to develop it. Some are just stronger than others and don't ever develop it. However, if you are worried it doesn't hurt to go ahead and use the "fungus clear" which doesn't seem to stress fish and would be OK.

But I would go ahead and wait and just keep up with the water changes and good quality food which will boost their immune system.

I hope this helps!
Karen~