Poe Lim wrote:
Don't change the water and clean the filter at the same time; you are
re-starting the cycling process. Ideally only change half the filter media

Says who? That's not true if you are using a canister filter with biomedia
that is handled properly. I don't change *any* biomedia.
Like I said before, the water parameters were/are perfect (no ammonia, no
nitrite), which is a sure sign the biofilter is workign properly.

--
Victor M. Martinez

http://www.che.utexas.edu/~martiv