Fiberglass and Gunite Swimming Pool Stain Removal
Posted by Rick Black on Fri, May 29, 2009 @ 07:17 PM
Seeing Stains in your Concrete/Gunite Pool or Fiberglass Swimming Pool?
The purpose of this article is to help you understand metal stains on the surface of a swimming pool. I have been in the swimming pool business for 20 years and have practical experience with the removal of metal stains from fiberglass pools using products formulated by Jack's Magic. Keep in mind that there are MANY other products out there formulated to remove stains. . .I just happen to have the most experience with Jack's Magic.
Why is there Iron or Copper in my water?
Iron usually comes from the iron pipes throughout most city water systems or from the water pumped from a well. Iron stains will usually be brownish or rusty looking.
all images courtesy of the Jack's Magic Website.
Copper, on the other hand, may come from the heat exchanger in your pool heater, or from the Copper-based Algaecide used to kill mustard algae, or from an ionization system left unchecked. .and sometimes copper comes from some mystical source that no one can seem to discover! Copper stains will usually be bluish to grayish in color.
My pool was fine yesterday. . .but now there are brown spots all over it. . .what gives?!
Water is able to hold some metal in solution. Think of your water like a sponge. A sponge is able to hold a certain amount of water. If you go over the amount the sponge can hold, the water will not stay in the sponge will overflow. Likewise, when there is more metal in the water than it can hold, the excess metal will "plate out" on the pool surface.
It's also important to note that water with a lower pH can hold more metal in solution than water with a higher pH.
Common Scenario: The pool water has Iron or Copper in it.The pH is 7.0 and all is well. Then you shock your pool using calcium hypochlorite (pH of about 13.5) and the pH rises and at the new pH the water can no longer hold this metal in solution. So. . .just like the overflow from the sponge, the metal will flow out of the water and onto the surface of the pool. If you lower the pH of the water, the metal will come off the wall as it goes back into solution.
Here's the Problem Though. . .The Metal is still in the Water, waiting for the pH to rise so it can stain your pool again. You must use a product to get the metal out of the water.
The Stain is in the pattern of Footprints, or Checkerboard, or 2'x4' frame, or Dancing Amoebas. . ..or. . .???
The stain may be in some sort of pattern, but the pattern is irrelevant. Don't concern yourself with the pattern. Concentrate on getting the pool chemistry right and removing the metal from the pool's surface and the water.
Ok. . .I get it. Now. . .How Exactly do I get rid of the ugly stains off my pool?
I have many successful stories with Jack's Magic Products. Jack's Magic products concentrate on stain and discoloration prevention and removal. There are other good products on the market, but at this time I will concentrate on what has worked in pools I have personally treated.
Step 1: Determine the type of Stain
There are a number of ways to accomplish this. Probably the easiest way is to use the Jack's Magic Products Stain Identification Kit. This will enable you to determine exactly what type of stain you have AND define exactly what product or combination of products will most effectively remove the stain. The directions with the kit are easy to follow too!
Step 2: Priming the Water Chemistry for Stain Removal
To maximize the effectiveness of the stain removal products, you'll need to adjust your water chemistry to the following levels:
- Chlorine - below 1.0 ppm (for Jack's Magic Stain Solution #1)
- Total Alkalinity - below 80ppm
- pH - below 7.2
- Cyanuric Acid(stabilizer) - below 70ppm
- Calcium Hardness - 200-400ppm
Step 3: Time to Get Rid of those Nasty Pool Stains!
Brown Stains - Probably Iron
Add 1 pound of Stain Solution #1 per 6,000 gallons of water. Wait 1 hour. Add 1 quart of Blue Stuff. (The Stain Solution #1 will remove the stain from the pool surface. The Blue Stuff will turn it into a gelatinous goop that your filter will remove.)
Blueish/Grayish Stains - Probably Copper
Add 1 pound of Stain Solution #2 per 1,000 gallons of water. Wait 1 hour. Add 1 quart of Blue Stuff per 10,000 gallons of water. (The Stain Solution #2 will remove the stain from the pool surface. The Blue Stuff will turn it into a gelatinous goop that your filter will remove.)
Step 4: Flush The Metal from the System
The metal should now end up in your filter and it's your job to get it out!
- Sand Filter - Backwash Everyday for 3 Days
- Cartridge Filter - Clean the Cartridge Everyday for 3 Days
- DE Filter - Backwash and Recharge Everyday for 3 Days
Will The Stains Come Back?
Unfortunately, if you do not prevent the stains from reoccurring, they probably will. If your source water has Iron or Copper in it, every time you add water to the pool you are also adding metals. You should use a Stain and Scale Preventative product each time you add water. You should also clean/backwash your filter regularly (every 7-14 days) to remove the metals from the filter. Just make sure to follow the directions specified on the chemical products you choose to use.
This Whole Thing is Causing Me A Lot of Stress!!
Maybe so, but it's not as bad as if the pool were leaking. . .right?! Just relax. .it's a swimming pool and it'll be fine! As a matter of fact you can make the stains disappear by simply getting in the pool, lying on a float, and closing your eyes. . . The stains won't harm the pool surface in any way. When you're ready. . .add a little of this & a little of that, and the stains will go away(at least for awhile!)
More Info About Jack's Magic Products:
Website - Jack's Magic
To Find a Local Retailer - 1-800-348-1656
Technical Support Form - Tech Support
And. . .of course you can always contact Trilogy Pools!