Alright look, if you have a big aquarium, in my opinion canister filters are the way to go. Canister filters are external filters that sit underneath your aquarium, and they contain a lot of filter media.
I Recommend These Two Series of Filters
Fluval FX4 and FX6
The absolute best canister filters on the market are made by Fluval, and they are called the FX4, the FX6. Both links link directly to Amazon, where you can check out the current price. Like I said, these are the absolute best, and I will specify that later on.
If you have an aquarium up to 250 gallons (1000 liters) you are good to go with the FX4.
If you have an aquarium an aquarium that is as big as 400 gallons (1500 liters) you should buy the FX6.
SunSun HW302, HW303 and HW304
They do have a major price tag, and I can image that you would like to have a canister filter that does not break the bank. Therefore another option is a canister filter from the brand called SunSun. The model numbers are the HW302, HW303 and the HW304. These filters get great reviews as well.
| Aquarium Size in gallons | Aquarium size in liters | Required filter |
| up to 75 gallons | up to 280 liters | HW 302 |
| up to a 100 gallons | up to 380 liters | HW 303 |
| up to 150 gallons | up to 570 liters | HW 304 |