my fish are very sick, i need answers asap :(

Question
QUESTION: i have two oscars and they are both very sick, one is black and one is white.  i think they have some sort of fungus because the black one has white ulcer-like stuff appearing on his body and a hole that developed on his fin.  the white one looks perfectly fine however he is white so i would not be able to see the stuff and he is lying on the bottom of the tank on his side.  i have been to petsmart and used the medication pimafix twice and it did not work.  i also used a medication that i think was called life savers, this also did not work.  i have also changed the water numerous times used water conditioners and my water keeps testing perfectly fine, however there is this brown sludge that has coated the filter that i keep trying to clean.  the people at petsmart are at a loss and my fish are getting sicker and sicker and i'm pretty sure they are close to their finals hours

ANSWER: Hi Kristen,
 I am sorry for not answering sooner; I am on the road travelling right now, and I just got internet access.

 The brown sludge is very bad.  What kind of filter is it?  Are you putting food into the tank that the fish are not eating?
I suggest you keep doing more water changes until the brown sludge goes away.

-- Ron
  rcoleman@cichlidresearch.com
  Cichlid Research Home Page <http://cichlidresearch.com>


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

QUESTION: Hello and thank you for responding.  My fish seem healthier but they still have these spots, as they have for at least two months now.  I have a penguin filter with the bio wheel and the wheel is digusting, on the package it said that the wheel is supposed to last a lifetime and never be replaced.  I have taken some of the stuff out of the inside of the filter and its more like my fish live in a gross lake rather than a tank that I clean, though the water is just a little cloudy.  I never give my fish any more food than they eat but I'm guessing that the sludge might have appeared when I kept taking out the carbon filter to medicate them, now its just a battle.  If I take out the filter the sludge appears but the medication (i've taken to using pimafix since its organic and they can stay on it for longer periods of time) is ineffective with the carbon filter in.

Answer
Hi Kristen,
  Personally I don't use any carbon for any of the 100+ aquaria that I maintain.  The value of carbon is debatable because it can essentially "fill up" very quickly and after that it doesn't do anything.  

 You should not have filter sludge.  Somehow there is way too much free organic material in your tank.

 You can rinse off the filter wheel to clean it.  You shouldn't need to, but something is not right in your tank.   

 Are you sure that the ulcer like symptoms are not bites from the other fish?  

 When you change water, do you use a gravel vaccuum (you need to)?

-- Ron
  rcoleman@cichlidresearch.com
  Cichlid Research Home Page <http://cichlidresearch.com>