(Photos taken in Orchid Garden Kuala Lumpur)
These are Moth Orchids, members of the genus Phalaenopsis.
These have succulent leaves and do not have pseudo bulbs, due to this reason they are not capable of storing food or water and may easily perishable when lacking water.
But again, too much water kills this plant, getting the right balance is very important.
Water not on the flowers (or any flowers) as it will cost the flowers to have short lifespan.
And avoid watering at the crown of the plant as that might also cause crown rot.
Just water the medium on the roots part only.
I found that a fan had been fixed just for this section of orchids especially the moth orchids. I guess air circulation is very much required for this type. (many of my photo's didn't turn up well as the flowers were constantly moving) So if you do buy this one, do place them were there is a good air movement taking place in your garden area.
Moth Orchid must be placed in indirect light area, they should not be placed under direct sunlight as it would damage the plant.
Also the healthy leaves for this types are dark green, the lime green or yellow means too much light. They need a lot lesser light compared to other sun lovers.
Its been said that if you place your hand against the source of light upon these orchid plant - you should find a indistinct shadow, any indication of sharp outlined shadow means that its in bright lighted area.