Interesting and informative, however I disagree with the video in regards to nitrates and how often a filter should be cleaned. He implies the filter will remove nitrates and that is not going to happen. You cannot have anaerobic (lacking oxygen) bacteria living in the same filter as aerobic bacteria. There is simply too much water flow in a normal filter to allow for anaerobic conditions to occur. Power filters are designed specifically for aerobic bacteria. The only exception to this is if you don't clean the filter for a long time and the water flow rate reduces to 1 or 2 drops per second. Then the filter will go anaerobic but the aerobic bacteria will die under those conditions. And your fish will probably die too if that happens.
If you want an anaerobic filter to convert nitrates into nitrogen gas, you need a separate filter that has a very slow flow rate, with less than 1 drop per second. That is 1 drop, not 1 litre, but less than 1 drop of water per second.
The other issue I have is with how often the filter should be cleaned. He recommends every few months or less often if you have a prefilter connected to the main filter. Personally I think filters should be cleaned at least once a month regardless of how clean they look. The gunk that gets trapped in a filter is primarily fish poop and all the aquarium water is flowing through that. The cleaner the filter and the less poop the water flows through, the cleaner the tank water will be, and the healthier the fish will be.
Now after having said that, the rest of the video is quite good and his explanation of where filter media should be placed, and in what order is very good.
You don't have to use the brown media he used. Any filter media will do and you can even have sponges in each compartment. They all hold bacteria. My personal choice would be several layers of course sponge in the bottom compartment. Then several layers of medium sponge in the compartment above it. Then a couple of the fine white filter matt on the top. Then you can shove bio-balls or whatever else you want in there.
This is definitely worth watching for anyone who has concerns about how their filter is set up, but disregard the bit about nitrates and only cleaning the filter once every few months
