Ever heard the term Acid Wash?

What is an acid wash you may ask? An acid wash is a term which we use in the pool industry which refers to pretty much exactly what the phrase says. With the use of acid, lots of water and chlorine it forms a chemical formula known as C₄H₈Cl₂S ( aka mustard gas ) 

This is a very toxic gas which is extremely harmful to your lungs and smell and should be handled with caution. So why use it on a pool ? Well among many chemicals available to us this is by far the most effective chemical used in today’s world to get marks off a concrete surface including chlorine stains off tiles as well as to get rid of any bacteria, algae and loose particles of pool plaster. But as with anything it does have it’s negative points and that is by acid washing a pools surface a thin layer of gunnite is taken away hence the reason one should not acid wash to many times and this should never be done on a fiberglass lining as it will destroy it completely.

An acid wash should be performed before marbeliting a swimming pools surface this will ensure all lose particles are removed and a proper bond is formed when applying the pool plaster.

What You Will Need

We always advise on letting a pool company do the acid wash but should you feel confident enough to do it on your own this is a basic guide on how to do it.

First of all you will need the following items:

• Large Bucket
• High Pressure Sprayer
• Hose Pipe
• 1-4 Pool Acid depending on the size of the pool ( Not dry pool acid )
• 1kg HTH
• Hard bristle brush / broom
• Gas mask
• Heavy duty gloves
• 2-3 man team

Instructions On How To Acid Wash

1. Once all the water is out the pool, begin by high pressure hosing the entire pools surface from top to bottom and the mosaic tiles as well. Make sure you get in all possible grooves and holes.
2. Next begin pouring the pool acid on the walls, floor and tiles. You will notice that it is a yellow color with a rotten egg like smell
3. Now on all the places where you have poured the acid begin sprinkling some HTH over the acid. You will then start seeing the acid begin to boil and this is where the gas which is emitted, be careful it is extremely dangerous on your lungs so do not breath it in!
4. The next thing to do is to start getting fresh water in the pool, just enough so that you can sweep the acid in a soap like paste.
5. Work from the deep end out making sure the acid and HTH get everywhere
6. Once this is done you can now high pressure house all the solution off the walls and floor.
7. You may now drain the remaining water and acid mix out the pool.
8. Allow the pool to stand for a few hours before filling it