Silentnight Geltex 3000 Astral King Size Mattress
The Silentnight Geltex 3000 Astral Mattress combines an 11cm Geltex and Ultraflex comfort layer with a dual layer of pocket springs, which means pressure relief on top and a medium-firm feel underneath.
- Medium-firm feel with cushioning on top
- Gel layer helps regulate temperature
- Cover helps guard against dust mites
£881.10
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Silentnight Geltex 3000 Astral Mattress
More available sizes
Mattress details
Mattress
Silentnight Geltex 3000 Astral Mattress
Size
Firmness
Medium Firm
Construction
Gel
Pocket Spring
Depth (cm)
36
Layers
2
Layer Details
Geltex comfort layer
An 11cm layer of Geltex and Ultraflex that gives pressure relief and total body support. It cushions your body while the springs below keep you supported.
Pocket spring system
A dual layer of 2000 Mirapocket springs and 1000 Ultraflex mini pocket springs. The two layers work together to give a supportive base beneath the comfort layer.
Layer details from beds2go-ek.co.uk product page, October 2026.
Key benefits
- More personal space: You each get 7.5cm more width than on a UK double, which means fewer nudges when one of you turns over in the night.
- Length for taller sleepers: At 200cm long, the UK king is 10cm longer than a UK double, so taller sleepers can stretch out without their feet finding the edge.
- Gentler early starts: If one of you is up hours before the other, the extra width puts a little more distance between the person leaving and the one still asleep.
- Cooler for two: The gel in the comfort layer is temperature-regulating, which helps when two people share a mattress and the bed tends to warm up through the night.
- Easy bedding to find: Standard king sheets and a 230 x 220cm king duvet fit, so you won't be hunting for unusual sizes.
This size suits you if...
You share the bed every night and keep bumping into each other on a UK double, one of you is tall enough that 190cm feels cramped, or you get up at different times and want a bit more room between you.
Consider another size if...
Your bedroom is smaller than our suggested minimum of 2.7m x 2.9m, or you want a soft, sink-in feel, because the medium-firm rating is the same in every size.
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FAQ's
What room size do I need for a Silentnight Geltex 3000 Astral UK king?
We suggest at least 2.7m x 2.9m, with 3.2m x 3.2m feeling comfortable. New build master bedrooms often look roomy when empty, then shrink once fitted wardrobes go in, so measure from where the wardrobe doors open rather than from the wall.
Is a UK king big enough for two people on the Geltex 3000 Astral?
For most couples, yes. A UK king gives 75cm each, which is 7.5cm more each than a UK double. If you both sprawl, a UK super king gives 90cm each, so the UK king offers 15cm less each than that.
Is the Silentnight Geltex 3000 Astral king size long enough for tall people?
At 200cm, it's 10cm longer than a UK double, which is a real relief for taller sleepers. The UK king and UK super king are the same length, so if height is your only concern, sizing up beyond a UK king adds width, not length.
What size is a Silentnight Geltex 3000 Astral king in feet?
It measures 5ft x 6ft 6in, or 150 x 200cm. The mattress is 36cm deep, so check that your fitted sheets have deep enough pockets to tuck under properly.
What duvet and sheets fit a Geltex 3000 Astral UK king?
Standard king sheets fit, and a 230 x 220cm king duvet gives enough overhang for two. If you're buying the mattress too, compare the retailers listed on this page.