A properly dosed salt water pool should be better on your sinuses then a freshwater pool. as it is more in tune withe the chemistry of your body. Salt concentrations in salt water pools are about the same as that found in your tears. Perhaps you should check that your chlorininator is not set too high. too much chlorine can lead to irritation in places like the sinuses.
Because the pressure underwater builds up to painful heights and pushes against your face, the deeper you go
Blisters in the paint job? Poor preparation was the result of that. Drain the pool, re-prep the pool walls etc and repaint. Hmm, why did you paint the pool? Was it painted before?
If its too high you have to dump water and replace it with fresh water be carefull to work out how much water you need to replace you wouldn't want to have to do it again. If the pool drain goes into the public sewers ensure there are no local rules affecting such discharge, or that you have the necessary consent.
No your pool is considered a closed system all the water that you add goes only to the filtering system and back. If you put in too much water you will overflow the edges and make your skimmer less efficient. unless you have a floating pool skimmer then the pool will be able to change level without affecting the efficiency of the skimmer.
Baking soda raises the Total Alkalinty of the pool without really affecting the pH. Pool industry standards say 80-120ppm is normal. Soda ash or sodium carbonate is used to raise the pH without affecting Total Alkalinity. The importance of Total Alkalinity is if it is too low, the water seeking its dynamic balance will sacrifice components in the pool surface to satisfy its demand. If the pool surface has a slick or slimy feel to it but otherwise the pool water is clear, chances are the T/A is low and you are feeling the calcium hydroxide leeching out of the plaster. Run your thumbnail up the wall of the pool and look for a powdery deposit accumulating on your thumbnail.
Yes, in fact green algae can make you sick. I learned that from a friend of mine that decided he could go in the pool and yes, he did get sick.I went in my pool (full of green algae) every day last summer and did not get sick. However, I didn't go under water and get the water in my sinuses very often. I'm pretty sure it depends on how healthy you are overall.
You can get in imediately without worrying about hurting your self.
Simply put any pool can be a salt water pool, even an above ground pool.
Chlorinated
The water polo team is in a car pool.
You have to treat pool water with pool chemicals and use a pool filter to get and keep the water clear.
Sunlight warms pool water
Add salt