Description
This 3.2–5.0 mm fraction is crushed glass designed for sand filter tanks in place of quartz. It filters more finely – from 5 to 10 microns, whereas quartz lets through everything below about 30. It is sold in 25 kg bags; if you filter and backwash regularly, no replacement is needed.
| Grain size | 3.2–5.0 mm |
|---|---|
| Packaging | 25 kg |
| Filtration level | 5–10 microns |
| Service life | 10–15 years and more, if the filter is well maintained |
| Recommended for | large filters with over 100 kg of media at the bottom of the tank |
| Type | glass filling – a substitute for quartz sand |
| Quartz sand for comparison | catches particles of around 30 microns |
| Fractions for smaller filters | 0.5–1.2 mm, as well as 1.2–3.2 mm |
Key advantages
- Finer purification: 5–10 microns versus around 30 with quartz sand.
- Durability: 10 to 15 years if you look after the filter, and sometimes considerably more.
- Faster and better backwashing than with sand.
- The cost pays off compared with replacing sand over the next 10 years.
Which filters need it
This coarsest fraction is for large filters whose tank holds more than 100 kg of media at the bottom. If you have a smaller filter, look for another fraction – the fine 0.5–1.2 or the medium 1.2–3.2.
Frequently asked questions
Is it suitable instead of quartz?
Yes – it is a full alternative with several advantages.
How long does it last?
Roughly ten to fifteen years with proper maintenance, and often more; regular backwashing makes replacement unnecessary.
How much does one bag weigh?
25 kg.
How does it compare with sand in terms of cost?
It is a good deal if you count how many times you would replace the sand over the next ten years.
I am not sure which grain size I need
Find out how many kilograms of media your filter takes and choose accordingly – over 100 kg means 3.2–5.0 mm.
See also: Wellness, Pools and Equipment, Filters and Treatment, Pools, Pool Chemicals, Pool Accessories.
