How to avoid zinc toxicity in aquaponics
Galvanized steel can cause problems in aquaponics systems, however; if you are thinking about using one for your aquaponics system, it could save you some trouble down the road to know what you are getting into.
Galvanized = coated in zinc
Galvanizing is a process where the manufacturer dips the metal tank in a bath of molten zinc at a temperature of around 840 °F (449 °C). This is usually to prevent corrosion over time and to provide a cheaper alternative to stainless steel.
What’s wrong with a little zinc?
Zinc is a common micronutrient for plants. This leads some people to think it is safe for aquaponics systems. While it is true that plants can tolerate pretty high zinc levels in solution, fish cannot.
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