Ammonia & Nitrite Question

[scuzzlebutt]

I have a 50 gallon aquarium that has been established for about 4 years now. (only a pleco) I was not aware of the tank cycle process and replaced the filtration system with a new one. (Fluval 305)
After about 2 weeks of continuous water changes (via gravel vac) and tests, I had no ammonia or nitrites present and less than 5ppm Nitrates.
I went out and purchased 2 Sunburst Plattys and introduced them to the tank. 2 weeks later I purchased 4 Cory Cats.
One week later and my ammonia reading has been steady at .25ppm and nitrites at .50ppm. The Nitrates are at 20ppm. Every 2 days I am removing about 10-15 percent of the water and have the same readings.
Should I remove more than 15% of the water?
The fish seem to be doing very well. Hearty appetites and very active. Should I be concerned about the levels and just keep doing what I am doing or is there something else I should be doing? Thanks.

 

[Big Vine]

Keep doing what you're doing, as long as those ammonia and nitrite levels remain relatively stable (15% water change every other day). If those levels start to creep up at all, then you'll need to change more water at a time (or more frequently).

Sounds to me as though your levels should remain fairly stable though. Just keep doing what you're doing, and wait until ammonia and nitrite levels hit zero before adding anything else to the tank.

Big Vine

 

[scuzzlebutt]

Thanks! Will Do.