Bigger Power Filter 400Gph harmful?

I have a 20gal tank with a Penguin Bio-wheel 200 power filter. Ammonia has
been rising slightly from 0ppm - .5ppm - 1.0ppm. I did an water change this
morning and the ammonia level has dropped to .5ppm. Now if I got the Emperor
400 with 400gph. Will it harm the fish?

That GPH would probably be overkill for that size tank, might stress your
fish by creating too much current, and its your ammonia problem would not be
solved. Sounds like your tank hasn't completed the nitrogen cycle yet. See
http://faq.thekrib.com/begin-cycling.html

What if I have a tall tank. 20" x 10" x 24h"?? I have a bio-wheel 200 and
rena 300/w air stone. Is that enough?

"E.Otter" wrote in message
link.net...
That GPH would probably be overkill for that size tank, might stress your
fish by creating too much current, and its your ammonia problem would not
be
solved. Sounds like your tank hasn't completed the nitrogen cycle yet.
See
http://faq.thekrib.com/begin-cycling.html

You could put that airstone into double duty. Adding a corner box
filter run by the airstone will give additional filtration without the
heavy current. Get a big one. They can be a bit hard to find though. I
prefer the Lee's medium or giant size.

Lilly