Although you can clean a pool without draining it, there are specific instances where draining your pool IS necessary. If your pool needs a repair that can't be done with water still in the pool, then you need to drain it only with the approval or supervision of a pool professional.
Vacuum to waste through your multiport valve to prevent clogging in your filters. Pool Brushing – Brush vigorously and repeat the process every 8 to 12 hours. This will remove any dust, stains, and dead algae from the black pool water and surfaces. Then vacuum the pool to remove the shock dust and dead algae.
You should not let your water line fall below your skimmer at any time. Therefore, you will need to put your garden hose in your pool to fill it up as you vacuum, or add fresh water again after vacuuming. Otherwise, leave setting on “filter” and turn pump on to begin vacuuming. You will not lose water this way.
Use a pool skimmer to remove large debris from the pool's water. This will help prevent the pool filter from clogging. Skim any floating items from the top of the water surface. Then stir up the water and skim as much of the leaves and other larger debris as you can from the bottom of the pool.
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.
If there has been a serious invasion of excess dirt and debris, you may also need to shock your pool. Vacuuming is recognized as the only way to remove sediment from the bottom of a pool.
Recovering Pool Water
Adjust the pH levels as well as the water hardness. 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.
Pool water turns green because of algae in the water. Algae can grow rapidly, particularly when it's warm like Summer, which is why it can surprise you overnight. This generally comes down to an imbalance or lack of chlorine in the water.
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.
Remember, rain is acidic. Hence, pool overflowing from rain causes the Alkalinity and pH levels to lower. Very low pH causes pool water to turn very clear and acidic, which destroys your pool surface and equipment.
You can purchase pool filter cleaner, but some pool owners choose to make their own. One method is to fill a bucket with warm water so that it's deep enough for the cartridge to be completely submerged. Then, add one cup of liquid dish soap or dishwasher detergent for every five gallons of water.
In an average sized inground pool, we would recommend 10 to 20 gallons of Liquid Shock. Liquid Shock in 5 gallon containers is the cheapest way to purchase Shock. One gallon of inexpensive algaecide may also be added. This should help kill whatever algae was living in your pool.
Use a pool brush to push all the sand to one area, or at least to a few concentrated areas. Set the filter's multiport valve to “Filter.” You can vacuum the sand back into the filter. Vacuum your pool manually, .
Use a pool brush to vigorously scrub any pool surfaces covered in algae, including the walls, floors, and steps. Apply a green algaecide according to the directions on the label. Let the water circulate for 24 hours, then brush the pool surfaces again. Vacuum or backwash to remove any remaining dead algae.
For light, thin calcium deposits, try using a soft brush (such as an old toothbrush) and a solution of vinegar and water. If that doesn't work, try cleaning the tile with a solution of water and muriatic acid (you can find muriatic acid at your local hardware or pool supply store).
Scrub Away the Calcium Carbonate Scaling
Calcium carbonate is relatively easy to remove the stain. Spray the buildup with a calcium releaser to help soften scum and make scrubbing that much easier. Then use a pumice stone or nylon brush to wash away the rusty water stains from your pool installation & maintenance.
The solution to maintaining a clear pool is to use readily available liquid bleach as your chlorine source. Chlorine bleach, as discussed above, is not bound to a stabilizer, so when you add chlorine bleach to the pool, it will go right to work killing microbes and sanitizing.