Pool Filter Media Change: A Complete Guide

What Is Pool Filter Media?

Pool filter media is the material inside your pool filter that traps particles and debris as water passes through it. The media sits inside the filter vessel and does the physical work of removing fine particles from the water before it returns to the pool.

The most common types of pool filter media are:

• Pool filter sand — the traditional choice, used in sand filters for decades
• Glass filter media — a recycled glass alternative that offers superior filtration performance
• Diatomaceous earth (DE) — used in DE filters, not interchangeable with sand or glass media
• Cartridge filters — use replaceable cartridges rather than loose media

This guide focuses on sand and glass filter media used in sand-type filter vessels.

When Should Pool Filter Media Be Changed?

Pool filter media does not last forever. Over time, the media degrades, becomes compacted, or loses its ability to trap particles effectively. Signs that your pool filter media may need replacing include:

• Cloudy or dull water that doesn't clear despite correct chemical balance and adequate filtration run times
• Increased backwash frequency — if you're backwashing more often than usual, the media may be breaking down
• Channelling — water finds paths of least resistance through degraded media, bypassing filtration
• Sand or media particles returning to the pool — this can indicate damaged laterals or severely degraded media
• Unusually high filter pressure that doesn't resolve after backwashing

As a general guide, pool filter sand is typically replaced every 5–7 years, though this varies depending on usage, water quality, and the specific filter. Glass filter media generally has a longer service life than traditional sand.

Always refer to your filter manufacturer's recommendations for guidance on media replacement intervals.

Glass Filter Media vs Pool Filter Sand

When planning a pool filter media change, many pool professionals and pool owners consider switching from traditional pool filter sand to glass filter media.

Glass filter media is made from 100% recycled glass and offers several advantages over conventional pool filter sand:

• Finer filtration — glass media captures smaller particles, producing cleaner, clearer water
• More efficient backwashing — glass media backwashes more effectively, using less water per cycle
• Longer media life — glass filter media significantly outlasts traditional sand before replacement is needed
• Reduced chemical demand — cleaner water typically requires fewer chemical adjustments
• Environmental benefits — made from recycled glass, supporting a circular economy

For a detailed comparison, see our guide: [Glass Filter Media vs Pool Filter Sand](/resources/glass-filter-media-vs-pool-filter-sand).

Fine and Coarse Glass Filter Media

Glass filter media is available in two grades — Fine (0.2–0.5 mm) and Coarse (1.0–2.0 mm) — which are used together in compatible filter systems.

Fine glass filter media (0.2–0.5 mm) is used as the finer filtration layer in compatible swimming pool filtration systems.

Coarse glass filter media (1.0–2.0 mm) is generally used as the supporting layer in compatible systems.

The required configuration — including which grades to use, in what quantities, and in what order — varies by filter manufacturer and model. Always refer to the filter manufacturer's specifications when determining the correct media configuration for your filter.

For more detail, see: [Fine vs Coarse Glass Filter Media](/resources/fine-vs-coarse-glass-filter-media).

How Much Filter Media Do You Need?

The amount of filter media required for a pool filter media change depends on the filter manufacturer, model, and size. There is no universal quantity that applies to all filters.

To determine the correct quantity for your filter:

1. Locate the filter make and model (usually on a label on the filter body) 2. Refer to the filter manufacturer's installation guide or specifications 3. The manufacturer's documentation will specify the required media type, grade, and quantity

Do not estimate or guess the required quantity. Using too little or too much media can affect filtration performance and may damage the filter.

For more information, see: [How Much Filter Media Does My Pool Filter Need?](/resources/how-much-pool-filter-media).

Replacing Pool Filter Sand With Glass Media

If you're considering switching from pool filter sand to glass filter media during a media change, glass media can be used in compatible sand-type filter vessels.

However, compatibility varies by filter manufacturer and model. Always check the filter manufacturer's specifications before switching media type.

For a detailed guide to making the switch, see: [Replacing Pool Filter Sand With Glass Media](/resources/replace-pool-filter-sand-with-glass-media).