Review on Lee's 🚮 Carbon Cartridge, Effortlessly Disposal-friendly by Karen West

They work great although I haven't really tried to compare them as my riser only fits these specific carbon cartridges. I usually rotate the 2 cartridges that come in the pack. Between uses I put the dirty one in boiling water to sanitize it, then let it dry completely and replace it with another the next time I clean the tank. I was able to do this 4-5 times per cartridge so I don't have to replace them as often. My goldfish have survived over 3 years thanks to this method (and regular water changes, feeding etc.).