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Natural Rapport Pet Friendly Ice Melt is a blend of, among other things, calcium chloride and magnesium chloride. This combination helps to keep the price low while maintaining much of the reactive oomph of calcium chloride. Benefits include refreeze prevention, fast reaction time, and reduced application rates as compared to magnesium chloride alone.
As you may have deduced from reading between the lines above, the blending or diluting of the calcium chloride reduces the exothermic reaction. Thus, the blended formula is less useful in extremely cold situations, maxing out its effectiveness around -5º F. That said, this stuff is a good compromise if you're looking for affordability, reasonable reliability, and considerations for pets. 

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Green Gobbler Pet Safe Ice Melt is fast-acting in conditions with temperatures as low as -5º F. The active ingredient Magnesium Chloride helps to prevent refreeze and, in contrast to calcium chloride, is considered to be better suited to concrete that is less than a year old. Additionally, this product poses less risk to pets and vegetation. Also, this product comes in a variety of sizes &#40;10 - 50 lbs&#41;, so there's a package to suit the needs of users ranging from the hardened northerner to the fair-weather lowlander. 
It's a fact that magnesium chloride is less harsh than calcium chloride, but, as a consequence, its exothermic reaction is not as energetic and thus is not as effective. As such, the Green Gobbler Pet Safe Ice Melt will be used in greater quantities to perform the same amount of work. In such cases, a hand seeder is an optimal tool to evenly distribute deicer across a surface. However, the fine grain of Green Gobbler is susceptible to clogging such tools. That said, this product is easy to clean up and less likely to agitate the skin of humans and animals when compared to calcium chloride. 

Green Gobbler Pet Safe Ice Melt is fast-acting in conditions with temperatures as low as -5º F. The active ingredient Magnesium Chloride helps to prevent refreeze and, in contrast to calcium chloride, is considered to be better suited to concrete that is less than a year old. Additionally, this product poses less risk to pets and vegetation. Also, this product comes in a variety of sizes &#40;10 - 50 lbs&#41;, so there's a package to suit the needs of users ranging from the hardened northerner to the fair-weather lowlander. 
It's a fact that magnesium chloride is less harsh than calcium chloride, but, as a consequence, its exothermic reaction is not as energetic and thus is not as effective. As such, the Green Gobbler Pet Safe Ice Melt will be used in greater quantities to perform the same amount of work. In such cases, a hand seeder is an optimal tool to evenly distribute de-icer across a surface. However, the fine grain of Green Gobbler is susceptible to clogging such tools. That said, this product is easy to clean up and less likely to agitate the skin of humans and animals when compared to calcium chloride. 

Ice Melt Comparison