• Purchase: Immersion heater • Considerations: When buying a portable immersion heater for troughs or buckets, safety is your overriding concern. Size is also important; get the correct wattage for the volume of water you’reyoure lookinglo to keep warm. • Options: Heaters for large tanks, which typically run betwbetween 1,000 and 1,500 watts, are available in sinsinking or floating varieties. Smaller heaters, suitable for warming a single bucket of water, run between 250 and 1,000 watts. Both types of heaters have similasimilar features. Look for models that shut off automatically when the desired temperature is reached, when the water level is low or when they are removed from the water. You’ll also want to see heavy plastic or aluminum casing around cords and a mechanism for keeping the heating element from coming into contact with the trough or bucket itself. • Cost: from roughly $40 for a single bucket heater up to $100 for a large trough heater.