I have mine set up in a (slightly crowded) community tank. My pair of Kribs took two months to spawn after I got them. I had almost given up on them. They literally just had their first batch yesterday. I found it definitely helped to use cold water when doing my water changes...I use cold water every time, the Kribs colour up right away and my Kuhli's go nuts too. The cold water simulates rainfall. I started feeding them twice a day as well (using smaller amounts) as I was told they are more likely to spawn if food is plentiful. Every time I do the water change they colour up and start really paying attention to each other and 'shivering' and the female follows the male around everywhere. There were a couple of times were I thought they might have spawned, the female was rarely seen out of the cave for about a week and the male kept darting at the other fish in the tank and hovering outside the cave. She finally came out, but then they started acting like normal again. maybe she did spawn and ate the eggs? I've hear that it is common in for the first few batches.
A couple weeks and water changes later, the behavior started up again and the male made frequent visits to the cave the female was in. When she finally came out she looked grayer and started behaving normal again, so I thought it was another false alarm...but I noticed that the males colours had gone more vivid then I had ever seen him. A couple days later I was feeding them and notices a bit of movement on the gravel...and i noticed about 10-15 little babies!, being closing guarded by the parents of course. Now I've gotta figure out what to do with them, I hope they don't get eaten by the other fish, or their parents.
So that's my experience with getting them to spawn, cold water changes, a moderate amount of food, and time. Next time you think they may have spawned, watch your males colours, I think that was the dead give away for me. Dunno if my info helps at all...
A couple weeks and water changes later, the behavior started up again and the male made frequent visits to the cave the female was in. When she finally came out she looked grayer and started behaving normal again, so I thought it was another false alarm...but I noticed that the males colours had gone more vivid then I had ever seen him. A couple days later I was feeding them and notices a bit of movement on the gravel...and i noticed about 10-15 little babies!, being closing guarded by the parents of course. Now I've gotta figure out what to do with them, I hope they don't get eaten by the other fish, or their parents.
So that's my experience with getting them to spawn, cold water changes, a moderate amount of food, and time. Next time you think they may have spawned, watch your males colours, I think that was the dead give away for me. Dunno if my info helps at all...
please see my other thread for details and I have some important questions 
