Sorry, Kim, I REALLY don't mean to get you all stressed-out again, but like I said, someone else had mentioned kidney stuff on one of these pages, too (might have been LoveThem, but I'm not sure), so just thought it might be something to look into, maybe now that Rohan's doing better.....and if you can do a free-catch with one of the vet's sterilized sample jars (I'd first sterilize a low plate, catch the pee, then pour it into the vet's jar for transport), he won't have to even go anywhere. You just have to get the sample in to the vet as soon as possible as after 6 hours max. the results aren't accurate. Also depends on whether your clinic can do the urinalysis themselves, or if they send it out to an independent lab. Mine did it right there, unless they were swamped.
Good idea about using shingles. That oughta do the trick nicely!
Funny you should mention water/water quality, as I've been getting interested in a certain Dr.'s work around this lately (I'm SO far behind in books to read!) since the 'energy' training I took last year is linked to this other doctor's work. (more on this below)
On a strictly biochemical basis, sure, minerals are absolutely essential to good health, but the types and amounts of each differ in requirements per species, so that can play a big factor. We used to use DE-mineralized Reverse Osmosis water, so it would be clean of any nasties like bad types of bacteria, toxins, chemicals, etc. But then I'd add a small amount of Himalayan Rock Salt sole (sole-ay) which contains something like 84 trace minerals to the large medical-grade jug of water. Mind you, Nissa very often ALSO wanted plain tap water - she seemed to like the taste best of ALL water types, for some reason.....and at least our local water is pretty clean, but I worried a LOT about all the dang fluoride and less about the chlorine (which can dissipate in about 10-15 mins. if it's not too 'heavy'). In her last year, I let her have whatevertheheck kind of water she wanted, though, as it made her happier and there was so much MORE to worry about later on.
But under the "if I'd only known then....." Regrets Department, I now contemplate what I might have done
additionally (and for FREE!) had I also known about Dr. Masaru Emoto's work with water. So, since you're already cognizant of how our emotions, which are also just another form of energy, can affect everything as well, here's some reading for you that you might wish to add to the mix, which follows the same idea. (and yes, I'd think that your own antsy-ness about the former watertank did, indeed, affect its quality)
This first link is to highlight all the books Dr. Emoto has written already, demonstrating many ways our thoughts affect water, and keeping in mind, our bodies are comprised of around 70% water.
Dr. Masaru Emoto - list of booksThis other link is to the extensive notes an attendee to one of Dr. Emoto's presentations took, which gives you a good overall look at what's going on with this work. It's extremely fascinating, and, as everything always is, it's all connected to every other piece of the puzzle.
Toronto Dowsers/Dr. Emoto So, you might just wish to add some positive 'signs' to your taps before you fill everyone's bowls. Now, if we can just come up with a way to make 'em as PRETTY as some of those furniture pieces, too!

And since you live near a body of water as well, you could also start 'treating'
that! Hmmm.....no idea about the bleach thing, though, cuz I never used the stuff (only "oxygen bleach" if needed), so my kids only liked the warmth from the dryer on the clothes and towels. As far as I know, most normally, bleach smell is avoided by cats, as it supposedly smells like another cat's pee to them....hence the experts telling us to never use any bleach (aside from its inherent dangers) or even vinegar (same smell for cats) for cleaning litterboxes, but to only use something mild like soap flakes or environmentally-safe dish soap or the like.
However, another simply lovely pic, to be sure! I feel like a snooze now.......