Mr Traders ATMAN AT-1100AF Aquarium Internal Filter (For Freshwater and Marine Aquarium) Power Aquarium Filter  (Biological Filtration for Fresh Water)

All filters have to be cleaned every 6 months for best output. The media in the filtration system is live media containing bacteria, hence has to be handled with care. Biological filtration is more important than Mechanical filtration. Internal filters are primarily made for smaller aquariums and used for small to medium sized aquariums. Internal filters are generally cheaper than External filters, and they are placed inside the aquarium to provide water movement and aeration.