I received the following question in a PM but am posting it here anonymously so it doesn't have to get asked and answered many times.
Chlorine is Chlorine
The first rule that you should have been taught is that chlorine is chlorine is chlorine, at least when it is in the water.
Chlorine and Cyanuric Acid (CYA)
Though it is true that Cyanuric Acid helps protect chlorine from being broken down by the UV rays of sunlight, it is not true that this is its only side effect. The CYA protects chlorine from sunlight via two effects. One is a shielding effect since CYA absorbs UV so that lower depths of water are not exposed to as much UV when CYA is present.
Richard
So, Richard, based on your (excerpted) comments, above, if my hot tub NEVER....EVER sees the light of day (we ONLY ever take the lid off after dark when having our relaxing, midnight (typically) soak......should plain old household bleach do the trick for us?
Bleach In Hot Tubs
in Hot Tub Water Chemistry
Posted
So, Richard, based on your (excerpted) comments, above, if my hot tub NEVER....EVER sees the light of day (we ONLY ever take the lid off after dark when having our relaxing, midnight (typically) soak......should plain old household bleach do the trick for us?