sorry for my ignorance, i am having delivered a new external filter in a few days, as the internal one is not sufficient. After reading some of the other posts i am a bit concerned.....
is it possible that the tank, which has been running for over nine months, could develop new tank syndrome when adding a new filter??
Just leave the old filter on, run the new one with it for a month or so and it will seed properly. Then if you so wish remove the other one or leave it on. The more filtration the better.
