Acid washing is an extreme form of swimming pool maintenance. In the instance that a pool has become severely neglected, acid washing can make it like new again. Leaving a pool untended for a period of months can result in mosquito infested green water which stains the lining of the pool permanently. No amount of scrubbing will ever remove such severe stains. Acid washing works to actually remove a portion of the lining to showcase a new layer underneath. Since a limited amount of lining exists, acid washing is not something that should be done regularly.
Muriatic acid is the main component in acid washing. It is applied to the emptied pool one section at a time. After setting for a few moments, it is removed by spraying it with water. Once diluted enough, the acid will no longer eat away at the pool. The acid/water mixture will flow down to the pool bottom where it must be pumped out. A portable fluid pump works well for this.
If the acid is applied for too long before washing, the lining can become permanently damaged. Replacing a liner is very expensive and should be avoided. For this reason, pool owners frequently have professionals perform the acid wash. While it might cost s couple hundred more dollars than doing it yourself, it is worth the cost.
If you do indeed choose to perform the acid wash pool scrubbing independently, care must be taken. Safety gear including long sleeved shirts, pants, gloves, boots and eye wear are essential. If the acid comes into contact with the skin, it must be immediately washed off. Eye damage is the most severe, so be sure to wear goggles which form a water tight seal around the eyes.
Acid washing will leave the liner rough and gritty. Sealer can be applied to make it smooth once more. The regular use of pool pumps, filters and chemical additives can prevent this from happening again.