I should probably buy a new/different filter, shouldn't I?
The filter is not the problem. If the fish in your tank are strong and healthy, then they can easily steer clear of your filter at a moments notice.
But since your ammonia and/or nitrite is high, this will cause the fish to be extremely weak, which would not allow it to swim away from the filter.
But I saw a picture of your filter in your other post, and I would recommend you go out and get an AquaClear 20 power filter! They are really good filters!
<a href="http/www.petsmart.com/product/index.jsp?productId=2754068" target="_blank">http/www.petsmart.com/product/index.jsp?productId=2754068</a>
The only thing is, I don't understand why this filter is $89.99? I can get the same one at my LFS for like $28.00! I would suggest you go to petsmart, or another fish store and have a look at this filter!
Wonderful filters!
-FHM