This our 3rd summer with our pool. The fiberglass has always been smooth until this summer which is now getting a rough finish that I assume is scale build up from our well water. Visually there is no difference but we can definitely feel the rough texture. Any recommendations on how to remove?
Scale buildup in fiberglass pool
- Thread starter mah2496
- Start date
- Jun 22, 2014
- 47,908
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
Interesting that you believe it's scale but visibly there is no change. Scale usually comes with some amount of color change. Before doing anything too drastic, I would lower the water level to expose the top step (if your ground isn't too saturated) and pour some muriatic acid directly on that exposed step. If it bubbles on that top-rough step, then it is calcium. If not, you have something else happening. If you confirm it's calcium-related, you might consider maintaining a slightly negative CSI level for a few months. You can find the CSI level of your chemistry on the PoolMath APP. Other than that, probably physically standings/buffing. There is a no-drain acid wash, but that can be risky if not done properly.
- Jun 22, 2014
- 47,908
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
Full. That's what I used during my test. Confirmed by Viking. It doesn't take long to tell if it's calcium, so it's a quick test.
Been a while since I started this thread. Finally getting around to opening my pool. My robot vacuum has been submerged for better part of a month and has the same build up which feels and somewhat looks like sand, same as my pool surface. I believe its calcium as you mentioned so I poured full muratic acid on a portion of my vacuum and it fizzed and cleaned away the build up.
So i assume the pool build up is calcium. Whats the best method to clear the build up since brushing alone does nothing?
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What is your current CH, pH, and TA? Usually lowering the pH to 7.0 will put the calcium back in solution.
You need to drop the pH to 7.0 and try to keep it there, and brush the pool daily. That will help remove the calcium from the walls of the pool. Since the pH is off the chart high, it may take several doses of MA to lower pH.