Copper sulfate, a naturally occurring and manufactured copper salt, is used as a fungicide on crops, as a pesticide to kill snails and slugs, and as water treatment to kill aquatic vegetation. This chemical has serious chronic toxicity with implications for agricultural workers and the environment.
1 Keep the refrigerator temperature at or below 40Â° F (4Â° C). 2  The freezer temperature should be 0Â° F (-18Â° C). 3  Check temperatures periodically. 4  Appliance thermometers are the best way of knowing these temperatures and are generally inexpensive.
Using a hygrometer, test the temp and humidity in a variety of places in your fridge, especially the vegetable drawers. You ideally want an average temperature in your refrigerator of about 4-5 degrees C (37-40 degrees F), and a temperature of about -18 to -17 degrees C in your freezer (0-4 degrees F).Youâll notice, though, if you test a variety of locations in your fridge, youâll learn where itâs coldest and where itâs warmest.ou ideally want an average temperature in your refrigerator of about 4-5 degrees C (37-40 degrees F), and a temperature of about -18 to -17 degrees C in your freezer (0-4 degrees F). Youâll notice, though, if you test a variety of locations in your fridge, youâll learn where itâs coldest and where itâs warmest.