I am impressed how swift LifeSource responded to my concerns. I met with Terry who came to my home on a Sunday and thoroughly explained what the different possible reasons for the rings in the toilets. We were able to device a couple plans to fix it based on previous customer comments and experiences. I am looking forward to the end result. Much to my surprise they assured me that when all else fail, they are willing to add another system and even refund my money back. I hope it does not get to this point as I have not lost faith in their product. Thank you.