Mechanical filtration is the first stage of any aquarium filter - removing solids before they decay into ammonia + dissolved organics. Common media: coarse sponge (catches large debris, 4-6 week rinse), fine sponge (medium debris, 2-3 week rinse), filter floss/wool (polishing, replace 1-2 weeks), filter socks (sumps, replace weekly). Maintenance rule: rinse mechanical media in old tank water, never tap. Replace floss when it crumbles. Avoid letting sponges get fully clogged - they lose flow + breed anaerobes. Reef-specific: filter socks vs filter rollers (Theiling, RedSea ReefMat) - rollers automate the process and reduce hands-on time.
Reviewed by the Fast Aquatics husbandry team · Updated May 2026
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