If your fish tank filter isn’t bubbling, it means something is wrong, and there can be a variety of reasons for this:
- An air pump that is not plugged in or malfunctioning,
- an airline that has slipped from the air pump’s outlet,
- a twisted or clamped airline can all cause a fish tank filter to stop bubbling.
Is a fish tank filter supposed to bubble?
There are two types of fish tank filters that are supposed to bubble:
- Sponge filters
- Corner filters
These two types of filters operate by means of an air-pump that forces air into the filter with an airline. The air then causes water flow through the filter material which can be sponge or filter floss or a variety of other types of materials. The air is discharged in the form of bubbles from the filter’s outlet.
A bubbling fish tank filter indicates that a sponge or corner filter is working properly providing mechanical as well as biological filtration. If the filter is not bubbling there can be a variety of reasons that cause it, and the solution to most of them are really simple:
Is your air-pump plugged in ?
It may seem obvious, but a fish tank filter that isn’t bubbling could be due to a faulty air pump that isn’t blowing air into the filter.
Make sure the air pump is turned on and plugged in. You will hear the hum of the air pump when it is working properly.
Is your air-pump on, but not working?
If your air-pump is on, but it is not blowing air out of the outlet, it can be due to a broken or pierced diafrham of the pump. Diafrham kits for air-pumps are cheap, and a quick fix for most air pumps that is not blowing air.
If the air pump does not come on at all, it may be due to a power supply problem, in which case it will be uneconomical to fix and will have to be replaced.
Is the airline connected to the air-pump outlet?
An airline might easily slip from the air-pump outlet. The air pump will then turn on, but air will not be forced into the airline, resulting in no bubbles emerging from the filter’s outlet. Make sure that the filter’s airline is correctly connected to the air pump’s outlet.
Is the airline twisted?
A twisted airline between the air pump and the filter can block airflow, preventing air from reaching the filter and preventing bubbles from exiting from the outflow.
If you use a clamp to control airflow from the airline to the filter, it might potentially block airflow if it is too tight. Check that the clamp is actually allowing airflow to the filter.
