Safety concerns. Always marinate meat and fish in the refrigerator. You can use some of the marinade for basting after removing the meat or fish from it only if you bring the marinade to a boil and cook for five minutes to kill any bacteria.
Running the pump at night should only be when you are doing a major chemical treatment such as algae clean-up. Your pool is more vulnerable during the day, plants don't grow at night the way they do during the day--that's true of ALL plants including Algae.
In winter, reduce the number of hours your pool pump runs by reducing the number of times you filter the water to one 4 to 6-hour filtering cycle every 24 hours. In summer, reduce the number of hours your pool pump runs from 10 to 6 hours per day - research has shown that 4 to 6 hours per day is enough to keep your pool clean.