Danny, those are normal color variations in those leaves. If they are otherwise healthy, I don't think you have a problem. Wait a while and green will come to most of the leaves though the streaks will stay. PH levels are a real problem if you have fish. They are very sensitive to PH changes and PH is very changeable. What you need is a PH Buffer. A buffer prevents rapid changes in PH. There are a number available off the shelf. Muratic acid is not a good choice. It does nothing except give you a rapid change in PH levels that doesn't last and can be dangerous to keep around. A good buffer should last a long time but most additives require that you test frequently. Personally, since I don't like adding stuff too often, I use POP, or Plaster of Paris Calcium carbonate) slugs. I make several at a time and drop them in the water where there is a good flow. The POP has a chemical reaction with the water and as it slowly disappears it stabilizes the PH. In my pond it takes weeks to disappear and I can see it is still working. The big problem is that it is getting difficult to find POP without additives so not everyone likes to use it. I haven't had any problems. Bicarbonate of Soda is probably a better choice. I am posting a link below that gives an excellent discussion of the subject. Here is a link that might be useful: PH buffering

catherinet, I had water hyacinths in my pond this year for the first time with my water lilly, and it didn't spread like it usually does, it did bloom, but no spreading, I think it was the hyacinths. The water iris I have is not invasive, so it really didn't bother the lilly. I only fertilzie the lilly once in spring with tomatoe spikes in the clay in the pot. It bloomed all summer. I am not placing water hyacinths in the water next year. I'm going to let the lilly spread out a little more. I think they do affect the sun hitting the lilly through the water. I could be wrong, but I did notice a difference this year.

In many areas Oriental lilies benefit from some afternoon shade. IF it is really hot and sunny in that spot then they may need extra water. Lilies yellowing/browing up from the bottom is often lack of water. I seriously doubt the cat has anything to do with it. Poop generally fertilizes rather than damages.

In a word - YES. You could have purchased new equipment for the amount they have charged you to move it. Call around and speak to other water treatment folks in your area. Look for industry standard rather than proprietary equipment. Kinetico quality is quite good. They are, however, much mor expensive. There are others out there that will provide the same result with much less expense. As long as you're looking, get your own testing done by an independent lab and size your softener accordingly. Softeners aren't just cookie-cutter. One size does not fit all. What worked for you before may not be what you need now.