Discus require very good water quality! so I would think the RO water is excellent from them for orchids because its not very salty, and it contains nutrients too. Just don't give them the fish poop... I do wonder if the RO water collects some minerals from the pebbles in the tank.
Phrag besseae! These are the compact phrags I have: Phrag Waunakee Sunset, Phrag schlimii, Phrag pearcei and Phrag Ecua-Bess(really similar to Phrag Olaf Gruss). Phrag schlimii is a species that gives pink blooms and hybrids, and is also compact. I will get a Phrag Scarlet O'Hara eventually. Phrag warscewiczianum (aka Phrag popowii) is a compact long petalled species I have