best way to keep ammonia down during cycle

Question
Dave

Some may think this is a homework question but I read so many different opinions which is the best way in your opinion.

I moved my one oscar to a new tank a week ago. The tank was up for 3 weeks so its been up for 4 weeks now.  I used the seeding way to cycle with fish food. I also added sponges and beads rocks and filled the new tank with the old tank water at the beginning.  My readings are ammonia .50 (slowly rising) Nitrites 0 Nitrates .40-80  Ph 7.0. I did a 20%  water change(lighly vac on rocks)on wed of this week the ammonia stayed the same.   What is the best way to lower ammonia during cyle? without disrupting the good bacteria.  water changes or use Amquel? I read all sorts of different opinions. If I do water changes on the new tank can I use the old tank water to fill the new? or tap. What is your opinion to best deal with the cycle. I have 2 filters and an air pump going. The Oscar ate the first few days after I moved him the last few he has not,he ate yesterday lightly but swims around fine.

thanks for all your help from a beginner who adopted 2 - 3yr old oscars, a few yrs ago.

Answer
Hi Fran:  homework or not... the real question here is what is causing the ammonia levels to rise and the answer to that question is there is decomposition in your tank.  Something is rotting. Find it, remove it, and the ammonia levels will drop.  In the mean time I would add beneficial bacteria to your tank.  I would also check the water chemistry on the old tank and see what it is.  dave