Well, personally i think a happy H.orientalis is a newt that is 100% aquatic, eats eagerly and breeds every year. I don´t know if you are aware of the origin of your new newts, so i think i should comment on it. They are imported from China, where they are captured in mass. The importation process is very rough on them, many die before even reaching the pet-shops. Sadly, the majority of shops offer inadequate or down right bad care for them, which only makes things worse. As a result, the survivors, by the time they arrive to the hobbyist, are severely stressed and often ill. Provided they are not in too bad a state, they will recover from the stress if they are given good care. They will need excellent conditions to recover, otherwise the stress will only become more accentuated.
Take a look at this caresheet:
Caudata Culture Species Entry - Cynops orientalis - Chinese firebelly
There´s also tons of information around the forum and specially in the Cynops section.
Basically you will need excellent water conditions (no less than 10 gallons of cycled water), mild temperatures (anything between 15-21ºC will be alright), peace and quiet and a good diet (earthworms should be the staple). With that, and a bit of luck, they should recover and eventually thrive. I personally recommend having LOTS of live plants. They love areas of dense vegetation, plus live plants are of great help in maintaining water quality.
Watch out for signs of stress, like leaving the water, erratic swimming, hyperactivity, lack of appetite...
A happy firebelly newt has a healthy appetite (actually, it´s often HUGE), very rarely if ever leaves the water, and spends most of its day doing very little (unless in breeding condition).
Good luck with your new newts
