What are the main types of aquarium filtration systems?
Written by
Hoang Long
Reviewed by
Prof. David Walsh, Ph.D.Aquarium filtration systems typically employ three basic concepts. Mechanical filtration collects all the solid waste particles that are floating around in your aquarium. Biological filtration relies on beneficial bacteria to detoxify ammonia concentrations. Chemical filtration strips the water of all the dissolved substances it has absorbed through a process known as adsorption. All are necessary to ensure a balanced home for your watery residents!
Mechanical filtration is your first line of defense in the battle against rubbish. Sponges and filter flosses trap uneaten food crumbs and fishpoop, and come in various densities to target specific particle sizes. Clean regularly, and you'll avoid blockages, but dissolved toxins are not removed. Your water will be clear again almost immediately.
Biological filtration is the cycling of the nitrogen that happens in your aquarium. Beneficial bacteria will colonise the surfaces of ceramic rings and bio-balls. These microorganisms then convert toxic ammonia into safer nitrates, which are subsequently converted into nitrites. Never, ever wash biological material in chlorinated water from your tap. Those colonies must be preserved at all costs!
Mechanical Filtration
- Traps solid waste particles between 5-100 microns
- Uses sponges, filter pads, and floss media
- Requires weekly rinsing to prevent clogging
Biological Filtration
- Converts ammonia to nitrites then nitrates
- Requires 4-6 weeks for bacterial colonization
- Operates best at 65-85°F water temperatures
Chemical Filtration
- Adsorbs dissolved toxins and impurities
- Uses activated carbon and ion-exchange resins
- Needs monthly replacement for effectiveness
Chemical filtration utilizes contact to extract from water what alternative methods fail to remove. Activated carbon is responsible for eliminating medicines from your system, as well as heavy metals and odors. Other resins remove impurities, such as phosphates. All of these degrade in just weeks, and so it is also essential to replace your chemical media regularly.
Good, balanced aquarium filtration systems combine all three methods. Use mechanical filtration first to strain out large debris before the water passes through. Place biological media in the areas where water naturally flows. Use the chemical only at the very end to polish the water before it is re-entered into the tank.
Good routine maintenance will keep your filtration system operating efficiently. Every week, rinse your mechanical media in tank water only; replace chemical cartridges every month, and rinse biological media only when necessary to avoid harming the bacteria living there. Never take all the filtration components offline at the same time; that could result in disastrous shifts in important water parameters.
Read the full article: Understanding Aquarium Filtration Systems
