Thanks for the reply and the recommendation, Doc.

I thought the purpose of the sequestering agent was to sequester the metals in a dissolved state, preventing them from redepositing as stains. Are you saying that is not the purpose of the agent, or that the agent does not do the job completely/permanently?

Should I skip the sequestering agent and only use the CuLator? If so, should I test my water to determine what ppm of metals I have and buy the appropriate CuLator or just purchase the 4ppm version?

Thanx again!