When a fish has hatched the most important period of fish live starts: building up their complete body. All organs are only with a few cells present, hormone system is not yet developed as their enzyme system. AND the immune-system is not present yet. It takes at least 6 weeks for the fish to “construct" their body. 6 weeks they are vulnerable for a lot of dangers like parasites and infections. The best feed available has to be given. During these weeks the need all our attentions in system where we can manage them and eventually can treat them, These systems are our swim-up systems for the first 3-4 weeks and the primary nursery systems. After 8 weeks (2-3 gram) we transfer the fish to the secondary nursery. Now the immune system is well developed this secondary nursery can be systems in open water.
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