Your fish tank's water looks somewhat cloudy and at this point, mechanical filtration seems like a good idea. Or, perhaps, you want to take the aquarium's clarity to the next level and want to see
Aquatic Experts Aquarium Filter Floss for Fish Tank
Why Filter Floss & Micron Pads? Explained
Premium rigid pond filter media is custom designed for use in Koi ponds and other outdoor water garden applications. This extremely durable black filter media material is lightweight yet incredibly strong at 1 inch thick. Its interwoven structure is rigid enough to handle the elevated weight and quantity of debris that are associated with an open outdoor pond containing large Koi fish. The Koi pond filter pad filters out the small contaminants to create crystal clear water.
Aquatic Experts - Classic Black Pond Filter Media, Coarse Koi Pond Filter Pad, Bulk Roll, 12 inch x 36 inch x 2 inch, Size: 12 x 36 x 2
Aquarium Filter
Cause (+ Cures) for a Fish That's Floating Upside-Down But is Still Alive?
Suggest some cheap but effective filter floss/pad
How to clean an aquarium filter - by NT Labs
Bio Sponge Filter Media Pad Aquarium Fish Tank Biochemical Cotton
Cause (+ Cures) for a Fish That's Floating Upside-Down But is Still Alive?