I've read that to mineralize filtered water one could add a few grains of brown rice to the bottom of the water container. I don't do this, and I wondered if it were true, but I take alfalpha every day and get minerals that way.

The water will absorb the silica and minerals from the rice, but the addition of organic matter also increases the risk of molding . So I would stick to silica or unrefined sea salt.

 Who knew water could be so complicated??? What is pure water? Is pure short for purified?

Yes, but there are different levels of purification. Plain old carbon and fiber filtration actually does not remove much. Then there is reverse osmosis and distilled waters that remove most impurities. Triple distilled purifies the water even further. Then we have ultrapure water such as type 2 water. Type 1 water is the purest water. It is so pure that its purity is not measured by parts per million of impurities. Instead it is tested through electrical resistance. At 18 meg ohm it is conisdered ultrapure. The lab up north is producing 22 meg ohm water, which is so pure that it is actually highly corrosive. 

Purified by a water filter? Therefore filtered water?

Yes, but still contains a lot of minerals and can still have some dangerous impurities such as the fluoride added to water.

I didn't explain my situation very well. I have 2 water filters. One is an alkalizer/ionizer, the other Home Depot type water filter. Is it beneficial to use the alkalizer/ionizer for the filtering and ionizing qualities? (specs on my unit in prior post).

Alkaline waters are not healthy as they neutralize the stomach acid. As stomach acid declines with age, the older we get the worse this problem can be since the stomach acidity will not be able to recover as easily. And water is ionized anyway as it hits the stomach acid. So it is just scientific wording to make the product sound more impressive than it is to boost sales.

Is it good to drink water that is ionized/negatively charged?

No. What they are referring to are the hydroxyl (OH-) ions in the water. Hydroxides are caustic and can damage to tissues.  Would you drink Drano (potassium hydroxide) or lye (sodium hydroxide)? Of course not. Well the lower level hydroxides such as calcium hydroxide (lime) and magnesium hydroxide (sold also as Milk of Magnesia) are still caustic and burn the tissues as well as neutralize the stomach acid. As an example, Milk of Magnesia is frequently used as a laxative. It works as a laxative because it chemically burns the intestinal wall. This stimulates a release of fluid in to the intestines and stimulates peristalsis leading to the laxative effect. And calcium oxide/hydroxide has a warning label on their packages to avoid skin contact again because it burns tissues.

Is negatively charged water a good antioxident source?

Actually just the opposite. Hydroxyl radicals (OH-) of alkaline waters are some of the strongest free radicals known. Again this is why they are so damaging to the tissues.

If so, I can turn the alkalinity down on my unit and still use it. If not, I can use my other filter. I'm thinking it's a good idea to mineralize your water when using any filters. Is that correct?

Except for carbon filtration which does not remove many minerals.

I would like a solution for my tap water so that I don't have to buy bottles of spring water ALL the time.

You best bet then woudl be an inexpensive R/O unit then add silica or minerals back to the purified water.