About my oscar

Question
Hi Lynda. Could you please help me. I just bought a baby tiger oscar a few days ago. I have a 30 gallon tank(i know i need a bigger one) and he looked great in the store. I took all the precautions that I knew about; right temp 76, water conditioner, cleaned the bottom rocks, bought a 3 stage filter, let the tank run for a few days before buying the fish. But he looks brown now and lethargic. I don't want him to die so any help would be greatly appreciated

Thanks

Ethan

Answer
Hi Ethan,
A tank must cycle for at least 3-4 weeks before you can add a fish to it.  Your water has not cycled, and your fish will die if you don't bring him back to the pet store, and ask them to either keep him for you, or ask for a credit.
The proper way to cycle a tank, is to buy a used sponge to fit your filter.  Squeeze out the access water, do not rinse it, and add it to your filter, and let it run.  After three weeks, check your water for ammonia, nitrites, and nitrates.  Your ammonia level should be zero, or safe, your nitrite level must be zero, or safe, and your nitrates should be low.  
A used sponge is good for a very long time, until it is old, ragged, and falling apart.  Never rinse your sponge under tap water as it would kill the good bacteria in your sponge.  Always rinse your sponge in water that you have removed from your tank when cleaning it.
You are right about the Oscar.  One Oscar needs 60 gallons of water to be healthy, and happy.  He grows very quickly, about one inch every month.  When kept in smaller tanks, his growth is stunted, and they eventually die a terrible death.  His internal organs have no place to grow, and the Oscar dies.  Vendors do not tell you this, they are there to sell, and couldn't care less.  The Oscar is one of the most mistreated fish on the market.  There is no cure for stunted growth.  I thought I would let you know this.
For now the kindest thing to do, to save him, is to put him in a cycled tank.
Lynda