Large Zip Bag 19" x 17" — 18L Zip Filter Bag | Seachem

The Seachem Large Zip Bag (19" x 17" / 48 x 43 cm) is a large-mesh filter bag with a corrosion-resistant zipper, designed to hold up to 18 liters of filter media. Its large size makes it ideal for bulky biomedia such as Seachem Matrix and Seachem Pond Matrix. Made of PVC with durable stitched seams, it eliminates the need for strings or ties and closes securely with its corrosion-resistant zipper.

Main advantages

• Dimensions 48 x 43 cm (19" x 17") — holds up to 18 liters of filter media
• Corrosion-resistant zipper — no strings or ties, quick opening and closing
• Large mesh (8 Mesh) — maximum water flow through bulky biomedia
• PVC material with durable stitched seams
• Resistant to bleach, caustics and acids

Use in reef and marine aquariums

The Large Zip Bag is specifically designed to hold large biomedia in sumps, cartridge filters, or filter chambers. Its large mesh (8 mesh) allows for unrestricted water flow around bulky media such as Matrix and Pond Matrix. For smaller media like MatrixCarbon, PhosGuard, or resins, use the Seachem Zip Bag Medium (12.5" x 5.5") or the Seachem The Bag (5" x 9.5", 180-micron mesh), which have finer mesh sizes suitable for these formats.

Technical specifications

• Dimensions: 48 x 43 cm (19" x 17")
• Mesh size: 8 Mesh (large)
• Closure: corrosion-resistant zipper
• Material: PVC
• Seams: sewn
• Capacity: up to 18 liters of media
• Resistant to: bleach, caustics, acids

Media compatibility

• Seachem Matrix
• Seachem Pond Matrix

Comparison of Seachem filter bags

• The Bag (5" x 9.5"): superfine 180-micron mesh, welded seams, ideal for resins (Purigen, CupriSorb) and all filter media
• Small Zip Bag (12.5" x 5.5"): 25 Mesh, zipper closure, ideal for PhosNet, PhosBond, PhosGuard, MatrixCarbon
• Zip Bag Medium (12.5" x 5.5"): 16 Mesh, zipper closure, ideal for PhosGuard, MatrixCarbon, denitrate, Matrix
• Zip Bag Large (19" x 17"): 8 Mesh, zipper closure, ideal for Matrix and Pond Matrix

Instructions for use

Place the desired filter media in the bag and close it with the corrosion-resistant zipper. Position the bag in the filter, sump, or filtration compartment to maximize water flow through the media.

Why choose the Zip Bag from ReefSolution?

The Large Zip Bag is the essential accessory for containing Seachem Matrix or Pond Matrix in a sump or large filter. For finer chemical media such as Seachem Purigen, Seachem PhosGuard, or Seachem CupriSorb, use the Seachem The Bag with its welded seams and 180-micron mesh.

Frequently Asked Questions

Can the Large Zip Bag contain fine resins like Purigen?

No. The large mesh (8 Mesh) of the Large Zip Bag will allow thin resins to pass through. For Purigen, CupriSorb, and other resins, use the Seachem The Bag with its superfine 180-micron mesh and welded seams.

What is the difference between the Zip Bag and The Bag?

The Zip Bag uses a corrosion-resistant zipper and stitched seams, and is available in three sizes and mesh sizes. The Bag uses a plastic snap closure and welded seams with a superfine 180-micron mesh, ideal for thin resins.

How many Matrix tablets can the Large Zip Bag hold?

Holds up to 18 liters of filter media. For Seachem Matrix dosed at 250 ml per 200 L of water, the Large Zip Bag can hold enough Matrix to treat a system of over 14,000 L.