15kg Coarse Grade Glass Filter Media - Virgin Activated Glass Media

15kg Coarse Glass Pool Filter Media | Virgin Activated Glass Media (AGM)

Coarse glass goes in the bottom of the filter. It protects the laterals and aids backwashing. The fine media sits in its own layer above it.

The basics

• What it is: 15kg bag of Activated Glass Media (AGM), coarse grade. Treated media, not plain graded glass.
• Grain size: ~1 to 3mm.
• Where it goes: first into the filter, in the bottom of the tank around the internal laterals.
• What it does: protects the laterals, supports the fine media above it and aids backwashing.
• What you also need: fine media for the layer above. See 15kg Fine Glass Filter Media.
• Pick up or delivered: collect from 10 Industry Blvd, Carrum Downs VIC, or have it delivered Australia wide. Choose from the variants.
• Fits: almost all existing sand and media filters, subject to the manufacturer's media specifications.
• Brands supplied: SensaClear, AstralPool or Zodiac, depending on availability.

Australian warehouse stock, not simply a drop-shipping listing.

Brand and grading information: We source glass filter media from the above brands and all are of the same quality. Having worked for the major manufacturers in R&D we know where to source the same products!

Fine and Coarse Glass Filter Media: Which Do I Need?

Most swimming pool sand filters converted to glass media require both grades. They do different jobs.

Coarse Glass Media (this product), ~1 to 3mm:

• Goes in first, in the bottom of the filter around the laterals.
• Protects the laterals from the finer media and from direct flow.
• Supports the fine media bed above it.
• Aids backwashing by allowing water to distribute evenly through the lower layer.

Fine Glass Media, ~0.5 to 1.5mm:

• Sits in its own layer above the coarse media.
• Forms the main filtration layer.
• Captures suspended dirt, fine debris and other fine particles.
• Provides the water clarity benefits of the glass filtration system.

Replacing all your filter media? You will generally need both coarse and fine grades where your filter specifies a layered glass media bed.
View Matching 15kg Fine Glass Filter Media

What Is Activated Glass Media (AGM)?

Activated Glass Media, usually shortened to AGM, is glass filtration media that has been treated after grading rather than simply crushed and screened.

What matters at the filter is the result: a media bed that holds fine material well, releases it cleanly on backwash and keeps its grading over a long service life.

Published Performance Figures for Activated Glass

AstralPool publishes the following for its Viron Active glass media. The figures are the manufacturer's own and apply to a complete, correctly configured activated glass bed:

• Filtration to 5 micron at a flow rate of 20m3/m2 of filter area, against 20 to 30 micron for sand and conventional glass.
• Up to 50% less backwash flow than sand or conventional glass media to clean the bed effectively.
• 30% faster clearing of cloudy water than sand or conventional glass in independent testing (CTM Centre Tecnologic, project PR13/0118).
• A permanent negative electrical charge applied during manufacturing, which conventional glass does not carry. Measured as Zeta Potential in millivolts, it attracts organic molecules and continues working across the pH range of pool water.

These are published figures for that brand, obtained under the manufacturer's stated test conditions. We supply SensaClear, AstralPool or Zodiac according to availability, and published performance data varies between manufacturers. Real-world results depend on the filter design, flow rate, water chemistry, backwashing and maintenance.

Why Use Coarse Glass in a Pool Filter?

A properly configured glass media filter uses differently sized particles to create an effective filtration bed.

Coarse glass is installed first, at the bottom of the filter tank, around the internal laterals. It provides a supporting layer for the finer media above and helps maintain the intended media arrangement during filtration and backwashing.

These larger glass particles allow water to move through the lower media bed while supporting the finer material responsible for capturing much smaller suspended particles.

Using the correct coarse support layer can help:

• Protect the laterals from damage and from fine media intrusion.
• Maintain the intended filtration bed structure.
• Support the finer glass media above the laterals.
• Allow water to distribute through the lower media layer.
• Support effective cleaning and bed expansion during backwashing.
• Maintain the filter's intended operation when installed to the manufacturer's specifications.

Remember: Coarse glass is primarily a support medium. The fine glass above it performs most of the fine-particle filtration.

Why Choose Glass Instead of Traditional Filter Sand?

Glass media is a well-established alternative to silica sand for swimming pool filtration. It combines durable glass particles with controlled grading to create an effective media bed in compatible pool filters.

Glass media is widely used in residential and commercial filtration because it offers several practical advantages.

• Clearer pool water: Correctly graded glass filtration beds can capture fine suspended particles effectively, helping maintain clean, clear pool water.
• Efficient backwashing: Glass media can release accumulated debris efficiently during backwashing. Depending on the media and filter design, this may reduce the amount of water required to clean the bed.
• Long service life: Glass is a durable, chemically stable filtration material capable of providing years of service when properly maintained.
• Less frequent media replacement: Glass media can offer a longer service life than conventional sand, depending on operating conditions and maintenance.
• Consistent particle grading: Media graded to defined particle-size ranges, so the bed you build matches the bed the filter was designed around.
• Treated surface: As an activated media it is processed beyond simple grading, unlike plain crushed glass.
• Existing filter compatibility: Many conventional sand filter vessels can be converted to suitable glass media without replacing the filter itself.

These benefits relate to a correctly configured glass filtration system. Actual performance varies with the media grade, filter design, water flow, backwashing and maintenance.

Product Specifications

How Much Glass Filter Media Do I Need?

The quantity of coarse and fine glass depends on the filter's model, internal design, diameter, lateral arrangement and specified media bed depth.

Glass media is not necessarily a kilogram-for-kilogram replacement for silica sand. Many manufacturers specify a different total weight and a particular distribution between coarse and fine grades.

Before ordering:

1. Identify the brand and model of your existing pool filter.
2. Check the manufacturer's glass media specifications.
3. Confirm the required quantity of coarse and fine media.
4. Check that the supplied media grading matches the filter's requirements.
5. Order enough bags to achieve the specified media bed depth.

Do not estimate the fill quantity simply by matching the weight of the old sand. The correct volume and bed depth are essential to proper filter operation.

Replacing Sand with Glass Media

Most suitable pool sand filters can be converted to glass media as part of a normal filter media replacement.

The old media must be removed and the filter internals inspected before refilling. Damaged laterals, distributors, seals or other components should be repaired or replaced as required.

Where the manufacturer specifies a two-grade arrangement, the coarse media is installed around the lower laterals first, followed by the specified quantity of fine media.

After reassembly, the filter must be backwashed and rinsed according to the filter and media manufacturer's instructions before normal filtration resumes.

Safety: Always isolate the pump, release pressure and follow the filter manufacturer's servicing instructions before opening the filter vessel. Never open or service a pressurised filter.

Frequently Asked Questions

What makes activated glass different from standard glass media?

Standard glass media is graded and bagged. Activated glass is treated after grading, and that treatment is what the AGM name refers to. Manufacturers who publish test data for their activated media report finer particle capture and lower backwash water use than sand or untreated glass.

Can I use coarse glass instead of fine glass?

Not where the manufacturer specifies fine media. Coarse glass supports the filtration bed and protects the laterals, while fine glass captures smaller suspended particles. Using only coarse material in a filter designed for both grades can significantly reduce filtration performance.

Can glass media replace silica sand in my existing pool filter?

In many cases, yes. Most conventional granular media filter vessels can accept suitable glass media, provided the manufacturer's requirements for grading, quantity and backwash operation are satisfied. Glass is not suitable for every filter design.

Will coarse glass make my pool water clearer?

Coarse glass supports the filtration system, but the fine media above it performs most of the fine-particle filtration. A correctly configured complete glass media bed can offer improved water clarity compared with some conventional sand systems.

Does glass media require backwashing?

Yes. Glass media filters still require regular backwashing and rinsing to remove accumulated dirt. The procedure and frequency depend on the filter design, pressure readings, operating conditions and manufacturer's instructions.

Does glass filter media last longer than sand?

Glass media can provide a longer service life than traditional silica sand, although there is no universal replacement interval. Media condition, contamination, water chemistry and proper backwashing all affect service life.

Do I need to replace the filter when changing to glass?

Generally not, provided the existing filter is serviceable and approved for the selected glass media. The condition of the tank, laterals and internal components should be checked during a media change.

Will I receive the brand shown in the photo?

Not necessarily. Depending on availability, we may supply SensaClear, AstralPool or Zodiac coarse glass media. Packaging, particle grading and product appearance can vary. Contact us before ordering if a particular brand or exact grade is required.

Order from Heater & Spa Parts

Heater & Spa Parts (HASP) is an Australian pool and spa parts specialist supplying filtration equipment, pumps, heaters, replacement parts and maintenance products to homeowners, pool service technicians and the trade.

We operate a retail store and warehouse at 10 Industry Blvd, Carrum Downs, Victoria, supported by interstate warehousing and distribution arrangements.

Choose Australia wide delivery or collection from Carrum Downs by selecting the matching variant above.

Need fine media as well? Shop 15kg Fine Glass Filter Media here.

Important: Check the exact media grading, bag quantity and filter compatibility before ordering. Product branding may vary with supply. Always follow the filter manufacturer's installation and servicing instructions.