Lava Lamp Colours: Mathmos Special Fills Explained

What is a Mathmos Special Fill?

Mathmos Special Fills are exclusive online events, often launched during the Spring and Summer seasons and hosted on the Mathmos websites, mailing lists and social channels. For a limited time, we offer rare, out-of-range lava lamp colours that aren’t available as part of our standard collection.

Each special fill lava lamp is a customised version of one of our classic lava lamp bottles, meaning you can have an exclusive lava lamp colourway in a classic model that not everyone will have.

How do Mathmos Special Fills work?

Mathmos offer a choice of out-of-range lava lamp colourways up for a vote on the Mathmos social channels and via our newsletter to let the Mathmos community cast their votes for their favourite option. We count the votes, and the winning colourway with the most votes goes on sale for a limited time only.

The response from the Mathmos lavalamp community is always incredible. We love seeing how close the votes get and how passionate everyone is about their favourite colours. It’s just another reason why these limited edition releases are so special.

Can you refill lava lamp bottles?

We’re currently unable to offer custom lava lamp refill services, so as a solution to this, we love to offer unique lava lamp colours for limited periods occasionally to allow customers to purchase exclusive lava lamp colours to restore their lava lamps, or you can choose from the current range.

Make sure you’re signed up to the Mathmos mailing list so you don’t miss out on future special fills and limited editions

Where can I buy a Mathmos Special Fill?

Special Fills are exclusively for sale on the Mathmos websites. As they are only available for limited time frames they aren’t around for long so grab them before they’re gone!

If you missed out this time, then don’t forget to join us on socials to vote on any upcoming special fills.

Quality lava lamps, Hand Made in Britain.

Once the winning colourway is chosen, the Mathmos Special Fill goes on sale for one weekend only. After the limited-time sale ends, each Special Fill lava lamp bottle is made to order.

Every bottle is hand-filled at our lava lamp factory in Poole, Dorset, using Mathmos’ unique, long-lasting lava lamp formula to create the highest quality British lava lamps on the market. Please allow 2–3 weeks for delivery as we craft each bottle with care, just for you.

Limited time only: White lava lamps

We offered a variety of white lava lamp colourways for the Special Fill in March 2025. The vote options were between these limited availability lava lamp colours:

Violet / White
Clear / White
Blue / White

Clear / White was the poll winner and were made available to buy across the Telstar, Evo, Astro Baby ranges and as spare lava lamp bottles on the weekend of 24^th – 28^th March 2025 only. As an additional bonus, these Special Fill bottles were eligible for our 30% Accessories Discount when you spend £57 or more to offer Mathmos customers the best price.

Will I be able to buy the same a special fill again?

We cannot guarantee if or when a Mathmos special fill lava lamp colourway will return so it’s always best to snap them up quick when you see them. We keep a very limited number of special fill bottles exclusively for sale at the Mathmos lava lamp factory showroom but these are available on a first-come-first-served basis, they make for unique gift ideas but don’t hesitate or you could miss out. Additionally, you may find the special fill colours come up on eBay from time to time but this is not guaranteed.