Choosing Between External and Internal Filters for Your Aquarium: Considerations and Benefits

Whether to choose an internal or external aquarium filter depends on your tank's size, fish load, and preference. Internal filters are cost-effective and ideal for smaller tanks, while external filters offer superior filtration for larger tanks.

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Should I use an external or internal filter for my aquarium?

Having owned both cold water, tropical, and marine fish for several years, I've often found myself pondering the same question - which is better, an external or internal filter for my aquarium? The answer isn't as straightforward as it might seem; it depends on various factors including the size of your tank, the number of fish you have, and the type of aquarium setup you prefer.

Why Are Aquarium Filters Important?

Before delving into the specifics of external and internal filters, let's first appreciate the critical role filters play in aquariums. Essentially, the function of a filter is to remove excess food, decaying organic matter, harmful chemicals, and toxins from the water. This is crucial because these elements, when left unchecked, can pose a health risk to your fish.

Besides, filters aid in the nitrogen cycle, which is a process that breaks down harmful waste products like ammonia into less harmful nitrates. In a fish care context, the role of the filter is often undervalued, but it significantly contributes to the longevity and overall health of your fish.

Internal Filters

Internal filters, as the name implies, are placed inside the aquarium. They are commonly used in smaller tanks, as they are easy to install, relatively inexpensive, and do not take up much space. These filters are typically attached to the glass with suction cups, making them easy to remove and clean.

However, one of the cons of internal filters is that they may not be as effective in larger aquariums. Given that these filters are usually not as powerful as their external counterparts, they may struggle to adequately filter the water in larger setups. In case of a larger tank or more significant bio-load, you might have to clean or replace your filter media more frequently.

Internal filters are great for smaller tanks, however cleaning is not usually an option forcing you to purchase replacement filters.

If possible, try looking for a filter that has a sponge which you can wash under warm water.

External Filters

On the flip side, external filters are located outside the aquarium. These filters have a higher filtration capacity and are more suitable for larger tanks or tanks with a heavy fish load. External filters have the advantage of not taking up any room inside the aquarium, which leaves more space for your fish and decorations.

Moreover, external filters often have more filter media and better biological filtration, which leads to healthier and cleaner water. However, they are generally more expensive than internal filters and require slightly more complex setup. It's also worth noting that external filters may be louder than internal filters, which might be a consideration if your aquarium is in a quiet space.

Most of my tanks use an external filtration system. I've personally tried the external filters with UV - however they never really performed as well as the UV in my pond and found them to be quite gimmicky.

What Should You Consider?

The choice between an external or internal filter will ultimately depend on your specific needs and circumstances. Firstly, consider the size of your aquarium. What size fish tank do you need? This is a question you must answer before deciding on a filter. For smaller tanks, an internal filter would suffice, while larger tanks would benefit from the higher filtration capacity of an external filter.

The number of fish you have also plays a role. More fish produce more waste, which necessitates a powerful filter - likely an external one. Furthermore, consider the type of fish you have. Some species prefer calmer waters, so a less powerful internal filter might be best. However, others might thrive in the robust flow an external filter provides.

Ultimately, the decision on which type of filter to use boils down to what works best for you and your aquatic pets. Regardless of the type of filter you choose, regular maintenance is crucial. Always remember to clean your aquarium filter regularly to ensure it functions optimally.

In Conclusion

When it comes to choosing between an internal or external filter for your aquarium, there's no one-size-fits-all answer. While internal filters are compact and cost-effective, they may not be suitable for larger tanks or a high number of fish. In contrast, external filters offer greater filtration power and capacity, but they can be pricier and a bit noisier.

In the end, the choice lies in balancing your aquarium's needs, your budget, and the comfort of your fishy friends.