Use a filter cleaner, or change the sand or cartridge if it's not been done in many years. Use clarifier to help coagulate suspended particles or use flocculant to drop particles to the bottom. Fill the pool high with water and vacuum the pool to waste, by setting a multiport filter valve to waste (sand or DE filters).
A pool can only be safe for swimming without a pump for a few days and a maximum of one week. The definite number of days the pool will be safe will also depend on the temperatures of the water, the weather at that particular time, the level of chlorine, and how clean the pool was before the pump stopped functioning.
Without proper maintenance and care, a dirty pool can cause recreational water illnesses (RWIs). These illnesses include diarrhea, ear infections, respiratory infections, rashes, and/or inflamed eyes and lungs. That may sound alarming, but a well-maintained pool leaves nothing to fear.
Close the pool for winter – but don't drain it.
In winter, the water in your pool is still your friend. Especially when properly winterized, it helps to protect the pool liner, keep it clean and prevent unnecessary damage from debris, harsh weather and other factors.
For a severely neglected swimming pool, the best way to clean it is to drain all the water, sanitize the pool shell to kill the algae, and refill the pool. However, about the only type of swimming pool that can be completely drained safely is a gunite pool.
You should open your pool when the temperature is consistently above 70 degrees during the day. This helps prevent algae from growing, keeps pollen from collecting in the water, and doesn't cost much more than opening later in the spring.
Baking Soda and Green, Blue, or Yellow Algae
You'll need to use an algaecide to kill the algae and superchlorinate your pool to clear the water. After this treatment, test your pH and alkalinity and add baking soda to raise alkalinity to at least 100 ppm and pH to between 7.2 and 7.8.
A nylon or rubber brush is the correct choice for scrubbing the sides of a soft-sided above-ground pool. A large pool brush makes quick work of the job, but you may need a smaller brush to clean corners. Once the particles have been removed from the sides of the pool, turn your filter back on and agitate the water.
Should the green be due to pollen, there may be little to do in the way of minimizing the discoloration short of erecting a building around the pool. Fortunately, assuming there are no allergies to the pollen, it is safe to swim in a pool with that as the cause for green water.
Use pool shock until the dark green water turns blue-grey. Make sure the filter is running throughout until the water becomes clear. Use a clarifier and flocculant to coagulate and drop particles to the bottom of the pool. Fill and vacuum the pool.
Drain the water down to no more than 6 inches from the bottom of the skimmer if you plan to use a standard floating winter cover. Use your pool filter, switched to the "Drain" setting, to empty the pool water.
Even with proper and regular pool maintenance, it's often necessary to drain your pool — completely or partially — every 3-5 years. Draining your pool often isn't necessary, especially if you're following a proper and regular maintenance program.
Brushing thoroughly 1-2 times per week will prevent these materials from having the time to create a stain. Brush to Prevent Algae: Every pool can grow algae, but plaster, quartz, and aggregate finishes are more susceptible.
Statistically, a pool without chlorine is more likely to make you sick because of the possibility of being exposed to the things not contained or killed by chlorine. Remember, your skin is porous, so microscopic impurities can pass through. A pool sans chlorine is akin to a big puddle of murky water.
The water should be clear and blue. Look for any cloudiness in the water. Make sure you can see all the way to the bottom of the pool, even the deep end. If the water is tinted green or it is cloudy, it may be contaminated with algae.