Chlorella is a single-celled green freshwater algae that's been around for more than 2 billion years that has many benefits for horses, including the following:

1. Rich In Nutrients

Chlorella is rich in protein, amino acids (including essential ones), vitamins (A, B, complex, C, etc.), minerals (iron, calcium, magnesium, zinc, etc.) and essential fatty acids.

2. Chlorophyll & Detoxification Support

Because chlorella has high chlorophyll content, it's often promoted for helping with detoxification: binding or assisting removal of toxins, heavy metal or pesticide residues.

3. Immune System Support

Antioxidants and other bioactive compounds in chlorella may help reduce oxidative stress, support immune function, possibly helping more during times of stress or after illness.

4. Digestive Health & Gut Function

Some report chlorella can support better digestion: aiding beneficial gut bacteria, helping with absorption of nutrients, supporting the digestive tract.

5. Liver & Kidney Support

Because of its detoxifying effects and nutrient profile, chlorella is often suggested for supporting liver and kidney function.

6. Coat, Hoof, Skin, General Condition

Better coat shine, stronger hooves, possibly better recovery or maintenance of body condition have been claimed. This is probably due to a combination of protein, minerals, and overall improved nutrition.

7. Support for Metabolic Health

Some sources say chlorella may help horses with metabolic concerns: supporting blood sugar regulation. improving metabolism. 

Serving Size: 20g (2.5 TBSP)

Provides: 70 Calories, 14g Protein, 1.5g Fat, 3.5g Carbs, 0.5g Fiber, 20mg Iron, 10mg Calcium, 6mg Magnesium, 0.5mcg Vitamin B12.

Feeding Recommendation: For average horses, start with 10-15 grams per day. 
Increase gradually up to 20 grams per day (2.5 TBSP). 

3 LBS = 2 month supply

Important Notes:
Chlorella can accumulate contaminants depending on how and where it is grown. Choose sources that test for purity. Cracked cell chlorella, such as this, is easier for horses to digest and utilize. Because of its high mineral/iron content, there might be risk for horses with certain conditions. Monitor carefully and start slowly. Introducing too much too fast may cause issues like gas, loose stools, etc. Use caution and always consult a vet, especially when horses are pregnant, lactating, or on other treatments.