Questions about breeding Colisa lalia (Dwarf Gourami)
My male Colisa lalia has serious ambitions to reproduce! At least he collects every loose plant bit floating around in the aquarium like crazy and carries it to his bubble nest. I have only experience with breeding Betta splendens so far and have to say that the Dwarf Gourami builds a far more compact nest. Unfortunately, he chose the front left corner where I usually feed. As he chases away all other fish and also is after the female, I think breeding might succeed this time. He built a nest several times before but abandoned it after two or three days.
this sounds good - I simply recommend feeding in another spot, at least for a while!
Should I catch the male and put it into a separate tank so it can build a new bubble nest there, or shall I try to take out the nest he already built, put it into another tank and then add the fish?
None of which, just let the fish build its nest where it does now!
I am not certain whether the female is ready to spawn, she does not look "thicker" than normal, but it also possible that she does not have too many eggs...
Yes, this is not always clearly visible.
How long does it take until the female gourami gets ready to spawn, or shall I simply see if she spawns?
I would just let things go their way!
Can I leave a breeding tank with Colisa lalia unfiltered? I want to avoid the larvae getting into the filter.
This is possible if the tank is well planted. On the other hand, an air operated filter such as the sera L 60 with a correspondingly weak air current hardly produces any suction at all, furthermore the sponge cartridge prevents fry from being drawn in (small fry even like to graze off the micro organisms that grow on the cartridge!)
How long does a Colisa lalia father guard his offspring? Only until they are swimming free, i.e. when do I have to remove him?
Yes, until the fry swims free, this does not take very long. Ideally, you siphon off or catch the better part of the fry when they are swimming free (do not catch them with a net, not even with a very fine mesh one, it is better for the fry to remain under water!).
Can I put small shrimps, e.g. "Amano shrimps", into the breeding tank as scavengers, or would the shrimps prey on eggs or larvae? In that case I would add snails (ramshorn snails, trumpet snails), or do these prey on the fry?
The so-called "Amano shrimps" are indeed suited, and so are snails. Both are no threat for free swimming juvenile fish.
Do the larvae of this species grow fast or slowly?
They do not grow very fast, on a scale ranging from 1 (extremely slowly growing) to 10 (extremely fast growing) I would give them a score of 3 - 4.
Dr. Bodo Schnell