First, you should have the water lab tested to make sure what exactly it contains. After this fit a sediment filter followed by a carbon filter. If you use 10" casings and replaceable cartridges this can cost less than $100 and is easy to fit at tank or under kitchen sink (preferable)
Tannins are caused by vegetation decaying and leaching into the water supply. To know if you have tannins or if it is insoluble iron run the well for a little while and fill up a white cup, if the yellowish color never disappears then you probably have tannins in your water. You are more likely to have tannins if you are located near a body of water or in a forest area. Hope this helps.
It is removed by filtering
Bordeaux Blush
You will need a particular filter according to exactly what is in the water. Often a simple carbon filter works, but you need a lab test to be certain.
The inner bark contains tannins, flavonoids, phenolic glycosides, and anti-inflammatory and fever-reducing salicylates. The high concentration of tannins may be responsible for relieving gastrointestinal disturbances
Bugle weed contains flavone glycosides, volatile oils, and tannins.
Because of the tannins in arctic and boreal land and water.
Tannins
The type of water that contains the lowest amount of chlorine is spring bottled water. Normally it contains no or little chlorine.
Well water will work best as it contains many minerals and nutrients that are filtered out of tap water.
Tea contains tannins, which react with iron ions to produce a black iron tannate precipitate.
Aloe vera leaves are fleshy and act as storage tissue. It contains carbohydrates, proteins, tannins and variety of acids.