Hi Jerome
Do look up celticfish's numerous posts, there are great info there on his L46 breeding program...here's some initial feedback.
A healthy zebra is black and white, solid colors. They rarely grow larger than 4". Aeration is preferred, good filteration is most important. While they come from fast flowing strong current biotope, this is not neccessary to be replicated in order to breed them in a tank condition. They do well in 28 to 30 degrees water and 7 pH give or take slide variations as long as it is not too sudden. Type of substrate or lack of is not important (again pH should not drop below 6).
Hope this helps.
Cheers
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