Seachem Zip Bag Large 19 inch x 17 inch

This Seachem Zip Bag is a corrosion-proof, string-free mesh filter bag that securely holds filtration media in place.

• Large-Mesh Filter Bag with Zipper.
• Corrosion proof zipper.
• 48 cm x 43 cm (19 inch x 17 inch).
• No Strings or Ties.

The Large Zip Bag™ is a mesh bag for holding filtration media. It is available in a 48 cm x 43 cm (19 inch x 17 inch) size, easily holds 18 liters of filtration media, and it comes with a convenient corrosion-proof zipper. It is ideal for large filtration media, especially bio-filtration such as Matrix and Pond Matrix™.

Specifications

Seachem item #1505. The Large Zip Bag: 48 × 43 cm (19 × 17 in), holding about 18 litres of media. PVC, stitched seams, closed by a corrosion-proof zip rather than a drawstring or a cable tie.

Mesh: 8 mesh — the coarsest bag Seachem make. That is deliberate. Seachem list its media compatibility as Matrix and Pond Matrix, and nothing finer: an 8 mesh bag will not hold Purigen or GFO, and is not meant to.

Where it sits in the range, from Seachem's own comparison:

The zipper is the reason to buy it. A drawstring bag has to be untied and retied wet every time you service the filter; this one does not, and the zip is corrosion-proof so it survives salt water and the bleach or acid soak that regenerating media involves.

Setup & Use

Fill it, close the zip, and put it where the water has to go through it. That is the whole instruction Seachem give.

Put it where water is actually forced through it rather than past it — a canister basket, a chemical filtration module, or the high-flow part of a sump. Media sitting in still water does almost nothing.

Do not pack it tight. Eighteen litres is its capacity, not its target. Media needs water moving around each piece; a bag stuffed to the seams simply diverts flow around the outside and the middle of it does nothing.

Match the mesh to the media. At 8 mesh this bag is for Matrix and Pond Matrix. Fine media will run straight through it — use a Zip Bag Sm or The Bag for those.

It is the pond-and-sump size. At 48 × 43 cm it will not fit inside most canister baskets. It is meant for a sump chamber, a pond filter box, or a gravity-fed biofilter.

Freshness & Storage

Every batch we dispatch carries a minimum of 6 months' remaining shelf life. Store this product in a cool, dry place away from direct sunlight, with the cap or inner foil closed tightly after each use.

Filter media and substrates carry no manufacturing or expiry date — their working life begins on first contact with water, not on the shelf.

Returns & Replacement

Returns are accepted within 7 days of delivery, provided the item is unused and in its original packaging. Manufacturer-sealed items cannot be returned once the seal is broken, and sale-priced items are not refundable.

If your item arrives defective or damaged, message us on WhatsApp with your order number — or email us, if you would rather — and we will replace it. Approved replacements are delivered within 3 to 5 business days. Transit damage is covered by insurance on every shipment. If tracking shows delivered but nothing reached you, tell us within 72 hours, which is the reporting window Indian couriers allow. Damage caused during installation or use is not covered; replacement spares for such cases are chargeable.

Full terms are on our Cancellation & Returns page.