No. Danios are Tropical Freshwater Fish.
No, all danio lay eggs.
GloFish are actually zebra danio fish that have been genetically modified. These fish live in rivers in India and Bangladesh.
Provided their water does not move out of their temperature range for too long they will survive.
If your tank is large enough, you could add albino corys or some mollies
Mountain stream fish. Cooler water, a good amount of water movement. They will adapt to various conditions.
oceans
Rainbow fish live in the oceans.
In the aquarium the Zebra danio (Danio rerio) will eat most good commercially available tropical fish flakes. Like nearly all fish they really appreciate a feed of live food (daphnia etc) and/or finely chopped earth worms.
Saol
pacific ocean
Saltwater fish live in the saltwater seas and oceans around the world.
Starfish live in all oceans.