I'm certainly happy with them. They look great and they're pretty interesting. The male will go from hanging out in the plants like a crotchety old man one minute, to playing in the filter output with the rasboras the next.
The female is way more interested in eating than anything else. She spends a lot of time eying things intensely to see it they're food. Usually they're plant roots or spots on the glass.
you will know when they start mating because the male will disappear for about 2 weeks while he fans the eggs. don't worry he survives just fine.
when the eggs hatch you will want to either catch the fry and move them to another tank or a breeder box in that tank. or catch the male and female and move them. since you have other fish in the tank, it would be best to catch the fry.
i managed to raise 3 males from eggs. there are some pvc tricks you can try if you are really interested in breeding them. i didn't try them, i just figured if i could raise a few great! and if not, oh-well.
they are still too young to breed, so don't worry about them not spawning yet. but when they do reach that age, bloodworms really gets them in the spawning mood.
as far as the cave space, they like a tight spot with one way in/out. generally under a rock.
I didn't know that they preferred a one way in one way out cave.. I just assumed they would want a tube.
What were you feeding yours? Mine don't seem to show much interest in flakes, but have been taking brine shrimp readily.
they don't really eat flake, or pellet. you can ween them over to it, but they prefer frozen or live. i fed bloodworms, brine shrimp (regular and spiralina), tubifex worms, and emerald entree. they really enjoyed it when (as a treat) i would cut up a wax worm, or mealworm and put that in the tank. i had to stop though as i had a otto get stuck in the exoskeleton of a meal worm and i almost lost him.
i may have mispoke if i said they prefered a cave over a tube. mine did not like pvc tubes,they would go in it if there was no cave available. however overall many people have had better luck breeding them using pvc pipe as caves. because you can remove the whole tube and place it in a grow out tank instead of trying to catch the fry with a net.
Small update: they've started trying to spawn. I caught them in the act trying to spawn in the back corner of the tank last week (not in a tube? C'mon you two!) then this morning I came down, fed the the tank an noticed I didn't see them.
I looked searched the tank for about 15 minutes before I remembered seeing the male come out from behind some Nymphoides sp. Taiwan over the weekend and being confused as to how I didn't see him behind it since there was a big rock there...
I got out my flashlight and found that some of the sand under part of the rock was gone and the pair were hanging out in a fish-made rock cave.
This tiny little "cave" is barely large enough to squeeze their bodies into but they fit, and if they're happy and they spawn, I'll forget that they've snubbed my tubes.