First and foremost prerequisite is that you must have a breeding stock that is made up of at least 2 mating pairs with each of the mature fish reaching about 12cms in length. For the fish tank used for breeding purposes the size must be large enough measuring at least 2 feet in depth and is about 1 meter in length. The surface of the tank water should be filled with floating plants such as Limnophila aquatica or Hygrophila difformis so that these will become a substrate for the eggs to attach to.
You can also consider adding dried grass collected from lawn or open fields and this is often a good idea because the covering actually serves two purposes. First, this is to protect the eggs from the attention of their parents which are known to devour their own eggs while second, dried grass are known to harbor infusoria which will later serve as nutritious foods for the young fish fry.
The water condition that houses the mating pair should be crystal clean. When the gourami fish starts to mate, the male will produce a seemingly random number of bubbles that rises to the water surface and when the eggs are released it will also follow this random fashion. This is in total deep contrast with other labyrinth species which will instead build a bubble nest on a single spot. A healthy pair of mating kissing gourami is capable of producing at least a few thousand eggs per spawn and the parents should be immediately removed once this is done.
After being released, the eggs will float and attach to the plants which we have put in earlier and after 4 days time period, the young gourami fry will be free swimming searching for foods. This is the time when you should ensure that they get the best diet that they deserve. I would suggest providing brine shrimps or microworms and apart from that, combine with fine crushed fish flakes to fill up their stomach.
Pink and Green Kissing Gourami Species Profile