Aquatop Polyester Filter Floss, 14 oz. Bag, Mechanical Filter Media (PLY-14)

Aquatop's 14 oz. bag of 100% Polyester Filter Floss gives you a ready supply of mechanical filter media sized for large aquariums, sumps, ponds, and multi-tank fish rooms that need an extended supply. Loosely pack it into your canister filter, power filter, sump, or pond filter box to trap fine, free-floating particulate — the debris that causes cloudy water and clogs biological and chemical media downstream. Soft, lint-free polyester fibers tear and cut easily to custom-fit virtually any filter, and the material is fully safe for both freshwater and saltwater aquariums. Because floss works mechanically rather than chemically, replace or rinse it regularly to keep flow rates strong and filtration effective.

Features & Benefits

•       100% polyester fiber for dependable mechanical filtration

•       14 oz. bag — sized for large aquariums, sumps, ponds, and multi-tank fish rooms that need an extended supply

•       Freshwater and saltwater safe

•       Tears/cuts to fit canister, HOB, sump, and pond filters

•       Loose-fill design preserves water flow while maximizing debris capture 

Why Aquatop Polyester Filter Floss

• 100% polyester fiber — a dedicated mechanical filtration media that traps fine particulate other media pass through, for noticeably clearer water

• Freshwater and saltwater safe — compatible with planted, reef, and pond setups

• Universal fit — tear or cut to size for canister filters, HOB power filters, wet/dry sumps, and pond filter boxes

• Loose-fill design — pack it as light or dense as your flow rate requires

• Available in three sizes — 4 oz., 7 oz., and 14 oz. bags to match tank size and change-out frequency

• Inexpensive, frequent-replacement media that protects downstream biological and chemical filtration from clogging

How It Works

Filter floss provides mechanical filtration: water is pulled through a loosely packed web of fine polyester fibers, and the tortuous path traps suspended particles as it passes. Because it's a physical strainer rather than a chemical or biological media, its performance is about surface area and looseness of pack, not chemistry — pack it too tightly and flow (not filtration quality) suffers. Rinse or replace the floss regularly; once it's visibly gray, matted, or restricting flow, it has done its job and should be swapped for a fresh supply.

Usage Tips

• Pack loosely rather than tightly — this maintains water flow while still catching debris

• Place in the mechanical filtration stage, ahead of biological and chemical media, so it protects those media from clogging

• Rinse in removed tank water (never tap water) if reusing between changes, to avoid killing beneficial bacteria that colonize the fibers

• Replace on a regular schedule (weekly to every few weeks, depending on bioload and flow) rather than waiting for a total clog

• Cut or tear to the exact shape of your filter box, canister basket, or media bag for a custom fit