• Ammonia and ammonium should be rapidly converted by aerobic nitrification into nitrite and then nitrate and finally into nitrogen gas. If this does not happen then either the aquarium is not fully matured or there is a problem with the tank's biological system, which can be caused by an excessive biological loading being placed on the system.
• If the pH is too low then the cause may be a too low alkalinity and/or a build up of carbon dioxide caused by insufficient aeration.
