New Oscar tank .. NEED HELP !

Question
Hello there, I have started a new oscar tank and its a 55
gallon. I have 4 oscars (2 tiger and 2 albino) and 2 picas catfish. The tank was ran for a week using 2 aqua clear
300's. The filters were setup with sponge on the bottom and
carbon on top. I then added the fish in the 2nd week. The
first few days were fine then things went horrible fast.
I tried so many things after I saw one tiger Oscar acting
weird. He was not eating or swimming with the rest. I was
told by my local fish guy to test the water with the 3
tests. I tested the ph first which was 6.8, I then tested
the ammonia which was between .25-.50 , then i tested the
nitrite which was 0 . I know that the ammonia was high so I
did a 50% water change and tested again, the same thing. I
added Prime water conditioner to the water and tested again
... same thing. Well about this time i was just fed up. I
then added some aquarium salt and ammonia tablets to bring
down the ammonia. I tested the water after and nothing, it
had the same level as before. I don't know what is
happening to my tank, its driving me crazy. I lost 2 fish
today, one oscar and one catfish. They seemed to have a ick
like thing on there fins. I removed them and treated the
tank with ick cure. I don't have a clue to what is killing
the fish, I have tried soo many things. I have tried to
reach out to so many people but what they say doesn't seem
to work. The way the oscars were acting was, they would
rest on the bottom of the tank and breathe very hardly.
I hope you can help as I am about to just give up this
hobby all together.

PLEASE HELP,
Shawn

Answer
Hi Shawn,
 The key to keeping an aquarium is going slow.  You should start with one fish, not four or more.  It takes a while (6 weeks actually) for a new tank to balance out.  Only then should you add more fish.  
Personally, I never test my water.  People rely too much on test kits most of which are highly inaccurate or people don't use them correctly.  On top of which, pH doesn't matter to many fish unless you have very extreme pH to your water, e.g., over 8 or under 6.  
  In general, you should do a 25% water change once a week, every week. That one thing alone is your best avenue to success.  
  Oscars do not move very well from one tank to another.  An oscar will often not eat for days or even a week or more after it has been moved and they often will sit on the bottom for several weeks after being moved. They are highly intelligent fish and it takes them a long time to get adjusted when their whole world changes. You need to be patient.  

 It is also essential to get your fish from a good pet store. I discourage purchasing fish from pet superstores or similar places. Go to a place that knows fish.  

 There is absolutely no good reason to add salt to a tank with oscars in it.  Oscars come from water with no salt content, in the Amazon.

 Think of a fish tank as a lot like growing a garden. It takes time and patience and the rewards are not immediate, but definitely worth the wait.

-- Ron
  rcoleman@cichlidresearch.com
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