You already had clean water with your cartridge filter, but the tedious and frequent cleaning and high costs brought you to Ego3. The Ego3 hot tub filter is better, cheaper, and much easier to clean. And it gives your water quality an additional boost.
Why does hot tub water become transparent instead of clear when using Ego3 hot tub filters?
This is simply explained and lies in the know-how that is in our filter medium, the filterballs. The filterballs have been developed and optimized over years for use in hot tubs.

The clarity of the water is measured in NTU - basically how many suspended particles are in the water. Normal, clear tap water has about 0.5 NTU. Tap water also contains suspended particles - not to be confused with dissolved parts like lime, magnesium, etc. These cannot be filtered because they are dissolved in the water, not suspended. Back to the suspended particles - both the cartridge filter and the Ego3 filter filter all particles approximately larger than 40 micrometers due to their structure. This is called the separation sharpness of the filter material. That means all particles larger than 40 micrometers simply get caught in the fabric of the filter material.
The magic effect - Zero Dirt technology - the technical revolution in hot tub filters
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Now, with the Ego3 hot tub filter, there is, let's say, a "magic effect" behind which a lot of development is involved in detail. Of course, we can't do magic, but it seems so and is truly a brilliant technical invention. Within about a week in the water, a microscopically small adhesive film forms on the fiber of the filter balls. Completely unnoticed by us and we can neither feel nor touch it, but particles smaller than 40 micrometers naturally have no mass and the micro adhesive film is strong enough for them. That's why these micro dirt particles "stick" to the fiber. So lightly that they hold on the fiber, but come off immediately when cleaning. |
This creates so-called "technically pure hot tub water" in the pool.
A hot tub operated with Ego3 hot tub filters achieves a clarity level of NTU 0.1 (the lowest measurable value). We call this the "Zero Dirt Effect." That is 5x clearer than normal hot tub water or even tap water.
What are the advantages of this?
- absolutely no more dirt in the water
- 5 times clearer water
- less chemicals
- no smell on the skin
- less frequent water changes, as no micro dirt accumulates more and more