As has been proven so many times in a wide variety of places Algae will grow anywhere it can regardless of local conditions
yes, coral reefs do grow well in high levels of oxygen.
When oxygen levels are high people tend to get a 'high' sensation. When the oxygen levels are low, it feels like you are going to pass out. There are other ways to tell, but generally you would need prodigious equipment, that is most likely very expensive.
lots of plants particularly water borne algae
Fortunately phosphates do not directly harm your fish, even at high levels. However, the algae blooms that result from elevated phosphates can ultimately cause problems for the aquarium inhabitants. For instance, green water can deplete the oxygen, which in turn can harm the fish.
lungs
Low oxygen levels cause vasodilation in systemic arterioles.High oxygen levels cause vasodilation in capillaries in the lungs.
Actually, plants as we know them today are not credited with generating the high levels of oxygen in Earth's atmosphere. This was created by photosynthetic algae that were using carbon dioxide as a nutrient source and releasing oxygen as a waste product.
It is a false statement that bacteria do not grow well in food with high levels of moisture such as meat and cheese.
No, it won't. This is because of Mars' extremely thin atmosphere, lack of oxygen, extreme cold, high levels of solar radiation, low soil nutrients, and a high amount of acids in the soil.
Under most circumstances nitrates encourage the growth of algae. Strangely, in some heavily planted tanks with high CO2 levels, higher nitrates seem to inhibit the growth of algae.
lungs
Through the process of photosynthesis algae and later plants used the energy of sunlight to convert water and carbon dioxide into sugar and oxygen. Oxygen levels rose until they reached a high point of 36% about 300 million years ago. Climate shifts and changes in life on Earth later caused some of that oxygen to go back into carbon dioxide, which was sequestered in carbonate rocks, and oxygen levels began to fluctuate. Currently, oxygen levels are at about 21% but that may change over the next few million years.