I'd stick with just one pair in that size tank, especially since it's a hex with less of a footprint. It's possible that one of the pair is infertile. If you only have 2 females in the tank with no males, that would be fine, but since you are trying to breed them, no. The pair that you have would harass any new krib that you might add.
I would try again with another pair. You could sell back your current pair to the LFS or rehome them or have another tank (mwah,ahh,ahh,AH!). Anyways, then you could try again with another pair. But, you'd need at least a 55g to have 2 pairs together, IMHO. After observing mine in a 75g, they really do take up a lot of space, and if you have any tetras or anything else in there, the kribs will also bully them out of their territory. I lost 10 diamond tetras learning this.
What are your other parameters? Mine breed successfully in water that is about 6.8-7.2 (colors are very close on my test kit) and hard (like 150-300 GH ppm hard) and rather alkaline at 180-300 KH ppm. I keep my temp at 80. They seem to really like the granite caves I got from someone on Pleco Fanatics. I can't remember the username off hand, but for some reasion zcliff is popping into my head.
I would try again with another pair. You could sell back your current pair to the LFS or rehome them or have another tank (mwah,ahh,ahh,AH!). Anyways, then you could try again with another pair. But, you'd need at least a 55g to have 2 pairs together, IMHO. After observing mine in a 75g, they really do take up a lot of space, and if you have any tetras or anything else in there, the kribs will also bully them out of their territory. I lost 10 diamond tetras learning this.
What are your other parameters? Mine breed successfully in water that is about 6.8-7.2 (colors are very close on my test kit) and hard (like 150-300 GH ppm hard) and rather alkaline at 180-300 KH ppm. I keep my temp at 80. They seem to really like the granite caves I got from someone on Pleco Fanatics. I can't remember the username off hand, but for some reasion zcliff is popping into my head.
