Hi Rotweiler, and welcome to the forum!
Has the pool supply house told you what minerals are in the water? Are they something you've added, or are they in the fill water? What kind of pool finish do you have--vinyl liner, plaster, gunite, etc?
The recommended test kit is the K-2006, and can be gotten for a very good price through the Amazon link in my sig. Try using the Google search feature linked in my sig, as well--it works much better than the v.bulletin search feature on this forum.
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