*. It is manufactured from aluminium oxide** by dehydroxylating it in a way that produces a highly porous material; this material can have a surface area significantly over 200 square metres/gram. The compound is used as a filter of fluoride, arsenic and selenium in drinking water.
The KDF 85 media already in the UltraStream will filter any possible activated alumina eluted from the fluoride removal media (Tests done in the EU show complete removal)
The UltraStream will remove up to 78% fluoride from water. The maximum amount of fluoride allowed in municipal water in Australia is 1.5 mg/L. This means the UltraStream would have 0.33 mg/L left of the fluoride in the UltraStream water.
*Activated Alumina is not made from Aluminium. This material will not harm those persons with Thyroid issues.
**Aluminium oxide (alumina; Al2O3) is the same chemical substance as sapphire and ruby (but without the impurities that give those gems their color).
Ion Exchange filters are often presented as fluoride filters. Unfortunately, although they do remove up to 60% of the fluoride from drinking water, they store it and once ion exchange reduces through usage, all the stored fluoride will be re-released into the water.