I have had my tank for around 4ish months now being new to fish keeping I didn't really research much about filter media (stupid I know). My fish tank has an internal filter and has a carbon cartridge and a ceramic cartridge. I have recently been researching the cartridges and have found out that you need to replace the cartridges but every website tells me different information. Some say I don't need to replace the ceramic cartridge at all and others say I do
So how often do I actually need to replace the cartridges?