Himalayan male cat has always drank lots of water but raised from kitten in Florida. A great deal of calcium in Florida's water. Could this have been the cause for the calcium stones in thebladder?

It's possible, but this is common in cats even without extra calcium in the water. No way to say for sure that the water is what caused this.

Once the surgery is done I would buy a filter for your water. You can get ones that you fill up and place in your fridge that are $20 or less. That will cut out some of the added things put into the tap water.

Good luck with the surgery. :)

Lived in Florida moved to Tennessee surgery performed in tn. Vet remarked how many more calcium stones in bladder surgeries he performed in Florida compared to any other state hehad a clinic. Could it be the high calcium in Florida's water the cause? Has anyone else noticed this?

Most stones are calcium oxylate which is formed through protein and oxylate rich food. No correlation between hard water and stones, at least in human studies. However giving a cat soft water, even through a Brita filter, is cheap and might possibly help.