A simple, reusable trap that thins out a bristle worm population overnight — no flashlight hunts, no tearing your rockwork apart. What a bristle worm actually is Bristle worms are segmented marine worms (polychaetes) that arrive in almost every tank as hitchhikers on live rock, frags or sand. They live down in your substrate and rockwork during the day and come out at night to eat detritus, uneaten food and dead tissue. Rows of fine white bristles line each side of the body, and those bristles break off in skin like fiberglass — which is exactly why you want a trap instead of your hand. Read the full breakdown on our bristle worm guide. Why you would want to remove some A modest population is genuinely useful. They are part of your cleanup crew, and they turn waste that would otherwise rot into something your filtration can handle. The problem is that they breed to match the food supply. Overfeed for a few months and you go from a handful of worms to hundreds, and that is when reefers start seeing the downsides: Big worms crowd corals at feeding time and pull food right off the flesh Very large individuals can irritate or damage LPS and clams they climb across A heavy population means a lot of biomass competing for oxygen and adding waste of its own They make hand-work in the tank unpleasant, because a brush against one leaves bristles in your fingers The goal is to knock the numbers down, not to eradicate them. Trapping a dozen large ones over a few nights makes a visible difference without stripping a useful animal out of your system. How to use the trap Bait it. Meaty food works best — a piece of raw shrimp, a cube of frozen fish food, or an algae wafer. Bristle worms hunt by smell, so the stronger the scent, the faster they find it. Set it after lights-out. They are nocturnal. Place the trap flat on your sand bed or wedge it between rocks near where you see them come out, and leave it overnight. Hold it down. Tuck it against rockwork or set a small piece of rubble on top so flow and snails cannot roll it over. Check the window in the morning. The clear top lets you see what is inside before you disturb anything. Lift it out and empty it into a bucket. Do not reach in with bare hands — use tongs or gloves. Rinse the trap, re-bait, repeat for a few nights until the catch drops off. Then fix what caused it Trapping treats the symptom. The population exploded because there was food for it. Cut back on how much you feed, siphon detritus out of dead spots during water changes, improve flow behind your rockwork, and keep your mechanical filtration clean. Do that alongside a few nights of trapping and the numbers stay down instead of rebounding in a month. Specifications Dimensions: 4.4" L x 2.3" W x 1.4" H Material: 100% reef-safe PETG with a clear window on top Colors: Black and orange Reusable: rinse and re-bait as many times as you need Designed, made and supported in-house in Chicago This is our V3 design, reworked around feedback from our own customers and the Reef2Reef community — a wider entry, a better one-way path in, and a window that actually lets you check the trap without pulling it out of the tank.
