SmartPak Smart & Simple Magnesium Oxide Powder Horse Supplement, 3-lb bag

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$39.95 Chewy Price
($0.26 /serving)
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About This Item

Details

  • This supplement provides 5,000 mg. of magnesium oxide per serving.
  • You’ll be happy to know that magnesium oxide can help promote a calm demeanor in horses.
  • Plus, this useful supplement also supports healthy muscles.
  • Help your horse maintain proper metabolic and nervous system function with this supplement.
  • This powder horse supplement features one main ingredient for simple and effective supplementation.

Ingredient Information

Feeding Instructions

Learn More About SmartPak From Our Team of Experts

Questions & Answers

2 Customer Questions


What is the shelf life of magnesium powder


How many days is each bag

Answer by ChewyJun 25, 2025
There are approximately 154 servings per 3-lb bag and about 515 servings per 10-lb bag.
4.8
Rated 4.8 out of 5 stars
52 Ratings

16 Customer Reviews



Rated 5 out of 5 stars
By Megan on Jul 30, 2025
Anonymous

So cost effective

Got 10lbs for the price of two months of this from SmartPak! Set for over a year for such a good price. I also like that this provides the same amount of magnesium

Got 10lbs for the price of two months of this from SmartPak! Set for over a year for such a good price. I also like that this provides the same amount of magnesium in a much smaller scoop than other brands that I have used, less powder in her food = happier pony! It would be better if this came in a tub instead of a zip bag (I don’t think it would hold up for over a year of opening and closing every few weeks, I prepack my own supplements) so I did have an old container that had powder in that I dumped this into

By Megan on Jul 30, 2025
Anonymous

Rated 5 out of 5 stars
By Taylor on Jan 17, 2025

Awesome price!

It has been difficult to find magnesium oxide for my horse since the Uckele one disappeared from the market last year. I was impressed by the price of this, and

It has been difficult to find magnesium oxide for my horse since the Uckele one disappeared from the market last year. I was impressed by the price of this, and it is definitely the same product as the Uckele one was. Buying the MGO in bulk saves a lot of money!

By Taylor on Jan 17, 2025

Rated 4 out of 5 stars
By Debby on Jan 8, 2026

good quality supplement

it seems to helping my horse but I wish it had a better container, the plastic with zip is not a good idea for heavy supplements and especially cold days, which

it seems to helping my horse but I wish it had a better container, the plastic with zip is not a good idea for heavy supplements and especially cold days, which make it hard to zip, and that is the reason for the 4 star review.

By Debby on Jan 8, 2026

Rated 5 out of 5 stars
By Kathy on May 23, 2026

Great product

Comfortable horses, happy owner. Great bang for your buck. Who isn't trying to save these days?

Comfortable horses, happy owner. Great bang for your buck. Who isn't trying to save these days?

By Kathy on May 23, 2026

Rated 5 out of 5 stars
By Susan on May 22, 2025

Exactly what we need and no more

I live in Michigan where the soil composition means horses fed local hay are magnesium deficient. This product provides exactly what I need to supplement my young

I live in Michigan where the soil composition means horses fed local hay are magnesium deficient. This product provides exactly what I need to supplement my young horse’s diet. I really like that it’s straight up magnesium with nothing more.

By Susan on May 22, 2025

Rated 5 out of 5 stars
By Patty on Mar 6, 2026

Magnesium supplement

My mare is eating it with no problem. I will see in a few weeks if it works well for her

My mare is eating it with no problem. I will see in a few weeks if it works well for her

By Patty on Mar 6, 2026

Rated 5 out of 5 stars
By Brittany on Aug 28, 2025

Loveeee.

Love this for all my ponies, and super affordable! Ships fast. Will forever use this product.

Love this for all my ponies, and super affordable! Ships fast. Will forever use this product.

By Brittany on Aug 28, 2025

Rated 5 out of 5 stars
By Hayley on May 8, 2026
Bliss
Bliss

Affordable and quality

Really helps my mare with her anxiety

Really helps my mare with her anxiety

By Hayley on May 8, 2026
Bliss
Bliss

Rated 5 out of 5 stars
By Angela on Mar 18, 2026
Ace
Ace

Smart and Simple Magnesium

Just started using but hoping it helps Ace

Just started using but hoping it helps Ace

By Angela on Mar 18, 2026
Ace
Ace

Rated 5 out of 5 stars
By Janet on Apr 18, 2026

Fantastic delivery time

Great product in timely manner

Great product in timely manner

By Janet on Apr 18, 2026