I have distilled my water for probably over 15 years now. There are a few details that are important to understand:

• distillation does reduce the water to a 99.9% pure state (at least using my distiller, also a cheaper one - by megahome). however, this means the minerals have been removed too and a negative charge state is created. this is useful for detoxification but not good to use long term. in particular it can cause a loss of minerals from your teeth.
• you will probably find that the water is acidic too, if you test with PH paper.

My solution to these problems is to use pharma grade bicarbonate of soda to raise the PH and to use liquid minerals to remineralise the water (concentrace works well). The end result is very clean mineral water that started out as tap water.

I worked out the cost of this process a while ago and saw that, roughly speaking (at that time), the cost to produce this home mineral water was cheaper than buying quality mineral water from a shop.

There are other ways to distil large amounts of water but they are almost never used. I may look at that in future.