it’s a freshwater green unicellular micro algae that produces the red antioxidant, Astaxanthin, under stress conditions.

regulates oxidative stress, reduces inflammation, and offsets the effects of sun exposure and pollutants.

Astaxanthin can also be found in many sea creatures, some microbes, and flowering plants.

Astaxanthin can help prevent premature aging, improve skin elasticity, moisture retention, and protect the skin from UV rays.

helps to prevent Alzheimer's disease and other cognitive disorders, or slow their onset rate.

can improve mitochondrial function and rescue kidney function as well.
for kidneys:
esterified astaxanthin from H. lacustris is highly effective at reducing chemical-induced nephrotoxicity (e.g., from antibiotics like gentamicin or toxins).
Studies on chronic kidney disease (CKD) models show that H. lacustris extract attenuates renal fibrosis by reversing epithelial-to-mesenchymal transition (EMT) and restoring mitophagy (a form of autophagy that removes damaged mitochondria).
In studies using rats with induced renal injuries, administration of H. lacustris extracts significantly decreased high levels of blood urea nitrogen (BUN) and serum creatinine (p < 0.01), indicating improved renal function.

good for eye protection too.
known for its ability to cross the blood-retinal barrier, providing antioxidant, anti-inflammatory, and neuroprotective effects directly to the ocular tissues.

This species is well known for its high content of the strong antioxidant astaxanthin, which is important in aquaculture, and cosmetics. The high amount of astaxanthin is present in the resting cells, which are produced and rapidly accumulated when the environmental conditions become unfavorable for normal cell growth. Examples of such conditions include bright light, high salinity, and low availability of nutrients.
Haematococcus lacustris is usually found in temperate regions around the world. Their resting cysts are often responsible for the blood-red color seen in the bottom of dried out rock pools and bird baths. This color is caused by astaxanthin which is believed to protect the resting cysts from the detrimental effect of UV-radiation, when exposed to direct sunlight. When red, the growth of this algae is slowed.