White Stains on Black Diamond Brite Surface

[jgbutke]

My 12,500 gallon year-round Florida pool was installed in 2003. The pool had a stunning black diamond-brite surface and a salt chlorination system. The water was tested regularly at the local Leslie's Pool Store, and I followed the instructions of the seemingly very competent manager and staff about when to add salt and the various chemicals to keep the pool healthy and along with regular (but not over-diligent) brushing, all has been well until this year. An unusually very wet rainy season led to a few attacks of brown and / or green algae stains mostly on the pool walls and corners. These were usually resolved within a week by alternately super-chlorinating with liquid chlorine and powder shock (usually 12 hours apart) over the most affected areas.

Sometime about midsummer I noticed large streaks of white stains at the bottom of the pool. The streaks clearly coincided with where the Zodiac automatic pool cleaner had missed vacuuming during the course of its normal run. It appeared as though these white streaks were the result of undissolved salt or chemicals (such as powder shock, alkalinity, hardness plus, etc.). I travel a lot, and always treat and super-chlorinate the pool with powder chlorine before I leave. I honestly do not know which of the white treatments (salt, shock, pH, etc.) I may have added before this trip that led to the white streaking, BUT the white streaking would NOT brush out no matter how aggressive I was.

Since then, the salt chlorination system has pooped out altogether, and concurrently the white deposits have spread and are adhering to all the black diamond-brite surface, although the original white streaks on the bottom are still more visible. (I am not going to address whether I am going to replace the salt chlorination system until I resolve the white staining problem, and until then am treating the pool regularly with combinations of liquid chlorine, powder, and floating salt tablets.)

The local Leslie's store manager suggested I perform a shallow water manual test where I took a small container of undiluted muriatic acid and isolate it over a spot area for a few minutes and brush immediately. THIS TEST WAS SUCCESSFUL, in that the pure muriatic acid followed by brushing seemed to remove the white deposit over the small test area. She (who always seems far more concerned with helping her customers resolve problems than selling more Leslie's products and services) along with an area "diamond brite" sales representative suggested I look into no-drain acid wash products.

CAN ANYONE PLEASE ADVISE HOW I CAN MOST EASILY AND INEXPENSIVELY REMOVE THE WHITE DEPOSITS ALL OVER MY POOL SURFACE AND RESTORE MY RECENTLY ONCE STUNNING BLACK DIAMOND-BRITE POOL SURFACE? Would any "no drain" acid wash products be effective? Should i just try very high concentrations of muriatic acid and brushing for several days before restoring the appropriate chemical balances? Any other suggestions?

[duraleigh]

The first step is to post a complete set of test results.

The results need to include:

FC = Free Chlorine
CC = Combined Chloramines
pH = pH
TA = Total Alkalinity
CH = Calcium Hardness
CYA = Cyanuric acid.


That'll give a good picture of your water chemistry and we can help from there.

[jgbutke2]

Sorry for delay in replying to your response asking for more info:
Water analysisnas of two days ago:
* Free available Chlorine (FAC): 5.0 (range is 1-5 ppm)
*Calcium Hardness (CH): 260 (range 200-500 ppm)
* Cyanuric Acid (CYA): 60 (range is 30 - 100 ppm)
* Total alkalinity (TA): 80 (range is 80-140)
* pH: 7.6 (range is 7.2-7.
* Copper: 0 (result should be 0 ppm)
* Iron: 0 (result should be 0 ppm
HELP PLEASE<BEFORE I DO SOMETHING STUPID AND /OR DANGEROUS!

[upool]

Were you able to correct the problem with the white stains on your pool. I'm having the same problem with my pool as well. Any suggestions on resolving this issue.

[worahm]

About 3 months ago, I noticed white, vertical streaks approximately 4 to 6 inchs long on the walls of my pool which is finished with blue, speckled Diamond Brite. A water chemistry check at Pinch a Penny indicated the water chemistry was within all limits including phosphate and salt level, except for chlorine which was slightly high.

Because the calcium hardness level was within limits but on the high side (300), Pinch a Penny suggested diluting the pool with fresh water to reduce the calcium hardness level.

Before draining water from the pool, I decided to try bushing the white streaks with a small SS brush. It took a little effort, particularlly in the deep end of the pool, but the brushing seemed to work. The streaks I brushed have been gone for over a month and have not reappeared.

Today, I notice addtional streaks, in different places but always on the wall, starting to form, so I am interested in how others have addressed this problem and more importantly, what is causing the white vertical streaks. At this point, I suspect a high/normal calcium hardness level is not causing the white streaks. Any commnets? Bill

[westcoastflorida]

I have had a black pool for 3 years now and the only way I have found to keep pool black is acid. First if you have a salt system do not let the salt generator run. I installed a bypass in my system so I can valve out my heater and salt system if you do not do this you will be replacing your $300 or so salt cell. My 15,000 gallon pool takes 3 gallons of acid for it to work best. I bypass system, clean filter and add 3 gallons of acid. Run pool for at least 24 to 48 hrs or until pool is black. Continuously brush pool during this period. Once you are satisfied with color of pool balance chlorine using liquid chlorine. When chlorine level is back to normal raise ph back up to normal. After ph and chlorine stable clean filter and run vacuum. Be sure you do not clean filter until ph is stable usually takes at least 24 to 48 hrs. If flow gets too low and ph is not back to normal just rinse some of the filter lightly to get your flow back. After a good vacuum clean filter and resume normal operation. I keep two filters for this and use the newer one only for normal operation I save the old one for the acid cleaning. I also soak the salt cell in vinegar to clean it while cleaning everything else. I will never get another black pool they look awesome but what a pain in the butt . I know this is an old post but good luck finding help with black pool's.