I was trying to get some information about Gourami them but could not find enough.
I will list a few of my own experiences.
Pearl Gourami is the most peaceful fish to keep as a pet fish.
The blue Gourami is the most aggressive and may grow bit big.
At breeding time male changes its colour in the belly to golden.
Then they are very aggressive and chase other males almost the entire day.
Keep only one male and many females is the best method when they are aggressive.
Male makes bubble nests.
Then the male mate and it squeezes the female belly by wrapping itself around the female.
Once eggs are squeezed they fall onto the base.
The male collects them and place them in the bubble nest.
If any of them falls he religiously collects them and place them in the nest.
For about 2 to 3 days male does not eat but guard the nest.
Female should be separated after mating and fellow does not allow even the females to come near the bubble nest.
No fish can come near at this stage and he should be kept in isolation.
When eggs start hatching male should be taken out lest he will eat all of them being hungry and have not eaten for three days.
Pearl Gourami is one of my favorite fresh water fish.
They are very hardy fish and very peaceful except during breeding time.
They get very friendly with you and this is the only fish (my experience when separating them during mating times) that come up and stay flat on your palm touching your skin with the feelers.
No other fish does this, only Pearl Gourami.
Blue are not that friendly.
But the can be kept with other species if only few males and many females are in the tank.
They will inter-breed and that is why one gets Blue, Brown, White colour shades.
Generally, they require a tank of at least 20 gallons, with lots of hiding spots and preferably lots of plants.
More space the better and they keep to their territory.
They possess a labyrinth organ that allows them to draw oxygen directly from air.
Most have elongated, thread-like fins. These feelers they use like antennae to touch and explore their surroundings.
In my case the skin of my palm.
Kissing Gouramis aren’t actually kissing – males fight by grappling each other by the mouth.
They’re a relatively easy fish to breed in captivity but caring for the young is very difficult till they are about 3 weeks.
Lay about 300 to 500 eggs.
Many die if not eaten by the hungry male.
If you can save 20 it is a good yield.
Water must be aerated without disturbing the nest.
I often switch off the aerator and water should be very clean.
Good luck with your brood.
My ones are breeding and I do not do anything except feeding the other companions.
I have a very big tank and enough space to hide.
In nature they are very shy and do not come up at feed times.
I drop the food pellets (floating and pieces reaching the floor) and know they are there since the next morning the food is gone.
I do not know how many of them are there.
May be 20 or 30 and I put six of them at the beginning.
There is no population problem.
They do control their inmates according to the space available unlike humans.
They do not need oral contraceptives from WHO.