Four Fine Mesh Media Filter Bags with Drawstring - 3 Inch by 4 inch  UNIVERSAL FILTER MEDIA BAG – Optimal for Activated Carbon (Carbon Sold Separately)! Aquarium mesh filter media bag is ideal for small filter media, such as our Aquatic Experts Classic Activated Carbon. Works with pelletized carbon, GFO, zeolite, peat, crushed coral, barley pellets, ammonia, nitrate, phosphate, and silicate removers and other types of granulated filter media. Will not work for very fine resins such as Purigen and CupriSorb, for these use our Extra Fine Mesh Media Drawstring Bags. SAVE MONEY - Our 4 pack of 500 micron high-flow mesh media bags fit perfectly in a variety of filters including canister filters, power filters, sumps, wet/dry filters and pond filters for your tanks. Just fill our economical bag with your favorite filter media. You will receive four 3 inch by 8 inch mesh bags. Also, available in 8 inch by 12 inch bag. DURABLE AND REUSABLE - These unique mesh filter bags are easy to fill and empty with top drawstring design to keep filter media secure. Our bags are durable, washable, and can be reused. OPTIMAL AND CUSTOMIZABLE - Place our high-flow drawstring mesh bags filled with your choice of media in flowing water. The mesh bags optimal hole size allows water to freely flow around and throughout the media. If you require a bag filled with media to be shorter; partially fill the bag, fold over, empty part and tie off. SECURE BAG CLOSURE: Our bags close tight to prevent loose media from potentially causing damage to your water pump or power filter's motor. The bag is 100% nylon and completely safe for both fresh and saltwater aquariums.   Our FINE MESH DRAWSTRING MEDIA BAGS are customized for optimal flow with all aquarium and pond filtration products including granular activated carbon, peat fiber, pellets, resins, and any type of biological or chemical filtration. These fine mesh bags are non-toxic and tested to ensure safety for all freshwater and saltwater aquariums, koi ponds, and water gardens. The very fine mesh keeps your favorite media secure and protects your pump as you clean and condition your water. The unique drawstring design makes these durable filter bags easy to use and reuse many times. Your new mesh media bags will simplify the use of chemical filtration in your fish tank or pond while saving money. Take the next step in perfecting your hobby, and make your aquatic friends happy with crystal clear water!