Repotting cattleyas

[Roberta]

First, Welcome.

I leave it to members who live in a climate similar to yours to recommend media and potting strategies. But one important item... using softened water was likely a "slow poison"... most water softeners replace calcium with sodium, which is horrible for plants. The calcium-containing hard water won't harm the plants at all. RO water can be beneficial, it may take some time to overcome the damage due to the sodium that the plants were exposed to prior.