often there is a seasonal change in water quality of municipal water sources. Also some water systems have seasonal scheduled filter changes/ system washing, that can add toxins to a system that are worse for fry. Starting with RO water or even good DI water and running it through a carbon pre-filter before you salt it up, will take care of these problems. It could also be related to the temp stability of you facility or where you produce food, or seasonal changes of who is working in your fish facility.
Our fish staff is great and we've worked through the water supply stuff, so don't see any "annual" die off. I'm guessing if you don't take it as "just something that happens" you'll figure out why it is happening, on the system in questions, and it'll stop happening
On Feb 18, 2015, at 11:43 AM, Donald Stedman wrote:
> Is anyone aware of "annual" phenomena of dyeing off of larval zebrafish? A group we are working with is claiming to have this problem and that it is occurring worldwide. Has there been any issue like this the last 4 months?
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