Types of External Filters

Aquarium external filters are a popular choice amongst aquarium owners mainly for their ability as good filtration devices combined with their control over the chemicals within the tank. While the shape and design of the filter depends mostly on the brand that is picked, there are two basic types of external filters that are popular amongst aquarium owners.

1. Classical External Filter: The more traditional form of external filter, this version contains an air-tight container with a pair of pipes acting as the inlet and outlet. Normally used for larger aquariums, these filters can be placed either alongside the tank or even under it.

2. Hang-On External Filter: This version, as the name suggests, contains a rectangular box that hangs on to the aquarium glass. The water flows into the filter through an inlet pipe however, it exits in a unique way. The filter curves over the edge of the aquarium’s glass walls and to release filtered water, it allows the water to fall over the sides and into the aquarium in a small waterfall-like manner. Extremely pretty to look at, they are meant mainly for small aquariums that are either open or have modified lids.

All external filters are easy to clean, making them the most convenient type. In classical aquarium external filters, there is the option of removing the filtration box, directly connecting the inlet and outlet pipes to maintain steady flow and clean the filter in some other room or outside. This prevents a lot of unnecessary mess indoors.

How do You Attach an External Filter to your Fish Bowl?

Once you get your hands on a filter appropriate for the size of your tank, the task is relatively simple. However, to choose the right filter, pick one that can filter the entire tank about 5-times an hour. Once you have your filter, assemble it according to the instruction manual accompanying it. Normally, this requires you to place the filter media inside the box and simple attach the inlet and outlet (if required) pipes to it.

Place the external filter so that the inlet pipe is submerged in the tank. The outlet pipe, if any, may be allowed to hang above the surface of the water so as to allow water to be poured back in. The last step is to plug the filter in and check if water flows through smoothly.

For better biological filtration, the output hose may be placed marginally above the surface of the water with a bio-wheel directly under it to allow biological filtration as well.

With this, your external filter is ready to go. In case of Hang-On External Filters, there is no outlet pipe and as a result, the filter’s external unit comes with grooves or hooks that allow it to be suspended on the outside of the tank. The water outlet needs to be placed appropriately to allow smooth flow of water out of the filter.

Although there is a marked difference in the way aquarium external filter types are installed, their functionality and working principle remains the same.