Yes you can add shock solution to your swimming pool after or at the same time as a clarifyer. You should not swim in your pool for at 4 hours after shocking it.
Yes, you should run the pump when you add chemicals to your water,
Pretty much --Yes.
The amount of chlorine normally used to shock a pool should kill and larvae and other living things in the pool.
Shocking a pool is increasing a the chlorine levels to the maximum, successfully.
Shocking produces gasses as a result of the chemical reaction between the shocking agent and the organic material in the pool water such as dead bugs, lipstick, and bodily discharges. It would be a good idea to vent off these gasses to the outside in addition to letting the humid air out.
You can't remove minerals in water either by filtering ( with standard pool filters) or "shocking" it. Run filter 24/7 until you are able to see the main drain at the bottom of the pool clearly then add your chlorine. You may have to do this (24/7 routine) each time you add large quantities of new make up water.
Shocking is not useful response for a broken pool thermometer. Most pool thermometers are electronic sensors or bimetallic strips, which won't put anything into the pool if they break, or are based on colored alcohol, for which shocking will not do anything. If your broken thermometer used mercury (unlikely) it will settle to the bottom and into the drain traps. You need to get the mercury out of the drains.
A pink or purple ring around the pool could be caused by minerals. You should try shocking your pool water.
Cl- too high? Wait a few days for the sun to burn it off. You could drain the pool and add some water, but that would be silly (imo). Cl- too low? Add liquid chlorine. Shock the pool if necessary (although shocking only gives a short-term boost to chlorine and adds to TDS).
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By shocking, it means to put a small amount of chlorine into the pool water, just to kill harmful bacteria. In most cases, it's safe to swim about an hour after shocking. Super-chlorination, however, requires at least 12 hours to allow chlorine levels to drop. Otherwise, it would be exactly like swimming in a pool of Clorox, and your skin WILL burn. That's why some pools are open 6 days a week and close the 7th day.
If you have a salt water hot tub or pool, you shouldn't need to add any extra chlorine. I am the pool operator at our local YMCA and we have a salt system with a Chloromatic chlorine generating cell. Rarely do we add any extra chlorine, only in cases of decontamination and/or shocking. Bromine does do better than chlorine in higher temps.