I have been doing my usual, putting off cleaning my filter media and was wondering what the logic is with doing so?
Water flow and oxygen levels. I use my canister filter for flow and to power other devices. It has a huge pre-filter, the gravel substrate of the tank, the canister works the uplift. I do not like sponge filters they clog up with microbial growth and have replaced mine with fired clay balls from hydroponics which are cheap and enable a high flow and decent dissolved oxygen levels to be maintained. I clean the canister out about once a year if I remember.
The canister output is split between a good UV unit (main flow) and the lesser flow feeds a ten gallon net trickle filter which has a spray head for a mist distribution onto again, clay balls. The unit is mounted above the level of the display tank.
The gravel substrate is siphon cleaned about once a month as part of general maintenance. Some parts are not cleaned that well because of plants.
It is the oxygen that makes the difference
With a good dissolved oxygen content you can smell the difference.
Trickle filters are the Rolls-Royce of filters for nitrification, they have a huge gas exchange surface area.
A tad wasteful on injected carbon dioxide but a small price to pay for a healthy bio-system. Would not be without mine, again a wholesome smell.
CO2 diffusion and flow distribution is via a dedicated in tank power head with high flow wire mesh intake screens.
Always keep an eye on the return flow rate, its a simple indicator of required maintenance.