In most cases, your filter media should need cleaning just a couple of times per year, so if you are finding that you have to clean the filter more frequently, then maybe it is time to look at your options.
Be sure to clean your filter media really well, manually remove the sludge, and squeeze out any smaller particles, as recommended, before placing them back into your filter unit. Never over-stock the filter box with biological media, because water needs flow and movement to get oxygen to bacteria, as well as to allow dead bacteria to fall off of the media. If you are having problems with the clarity of the water, which bio-media cannot clean, adding active charcoal to your filter box can alleviate this problem.
Ceramic rings should be added to the filter boxes in your aquarium to ensure dirty water will go into the mechanical filter, which traps any solid waste particles, and allows cleaner water to go into the biological filtration chamber, which eliminates the toxic chemicals released by the waste and other fish waste. If you have insufficient room for a filter to accommodate ceramic rings, they can be placed right into your fish tanks, in a gravel bed, where good water circulation is possible. Since they are non-harmful to the fish, you can use the maximum number that can fit into the filter, or put them into an aquarium bottom.
If you cannot fit the ceramic rings into the filter, put them into a nylon mesh bag and put the media bag directly into the water of your reservoir. It is best to pair flushing with water changes so that you can use tank water for flushing out your filter media. You do not have to replace the biological filter until it starts breaking down, but you may need to rinse it with tank water every month or so.
The mechanical filter media does not need replacing until it starts falling apart (in fact, replacing it would be more harmful than beneficial), but you will need to give it a rinse once a month or so in tank water. Depending on this, mechanical media will either sit on the top or the bottom of any given filter, as the water needs to pass through it first.
Beneficial bacteria, which serve as biological filters, will accumulate in the filter media, and replacing the media would completely remove these bacteria from the reservoir. Be sure to leave as much of the beneficial bacteria as possible in the tank when cleaning your filter or changing your filter media. A filter that is consistently getting clogged or is not removing particles might need replacing because your filter might be too small for your bio-load (waste levels), or the media itself might be damaged. In general, the filter needs to be cleaned once you notice the flow of water coming from the outtake of the filter decreasing, since that is a good indication of the mechanical media becoming clogged.
In addition to performing water changes every week, you will likely do one larger water change once per month, as well as replace your filter media. If your tank has a single sponge filter, you will likely want to clean that with each water change, which is typically once per week. If your filter has a biowheel or other biological filtering components, either suspend it over your tank or put it into a bucket with tank water so that it does not dry out while cleaning. Avoid using extremely hot water when cleaning filters, and also avoid using any soaps or bleach–all these things will kill your biological filtering system.
One thing that you have to be really careful about when cleaning a reservoir filter is making sure that you are not cleaning it too deep or too frequently. Note, weave recommended using aquarium water for cleaning the sponge filters, seeing as tap water is more than likely to contain elements such as chlorine which are detrimental for the fish, as well as killing any good bacteria within the filter. If biological media is clogged, cleaning it using normal tap water is okay (or you could use dechlorinated water), since in these oxygen-poor conditions, beneficial bacteria are likely not left behind anyway.
You can wash using tap water, and then rinse the filter cartridges carefully using the RO-filtered water, which removes any chemicals in the tap water. It is best to also regularly wash BioMax Ceramic Rings, whenever you are maintaining your filters, of any mud or debris that may prematurely clog your tiny pores, and, again, always make sure to use a safe, dechlorinated water that does not kill any of the active bacteria cultures that you are trying to keep alive. The BioMax ceramic rings may last about six months in your filter before the interior areas become clogged and exhausted with the proper locations for the beneficial bacteria, and they need to be replaced.
Ceramic rings, or any other medium, are always best placed in a filter as they come after mechanical media, and before chemical media. It is always preferable that the placement of ceramic rings or any other bio media in the filter is done in a specific sequence to maximize effectiveness. The media placed in a filter is kept away from coming into contact with waste particles, thereby maximizing bacterial assembly.
After one month, your filter media may still be good enough to serve as a decent bedding medium for the beneficial bacteria, but will not be able to clean up chemical impurities and stains as efficiently as they need to. For a better perspective; You might never have to replace your chemical filtration device unless it’s falling apart, but you’ll have to replace your filter media, which is, for the most part, carbon. If using ammonia removal products as well as carbon, changing the filter media to a new one should alternate, with filter service increasing to twice a week.