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Fiberglass pool calcium hardness

What is pool calcium hardness? - Best Pool Builder

Re: Calcium hardness and fiberglass pools I like to keep some calcium in my fiberglass pool, I usually keep it at around 125 - 150. Some say calcium is not needed for fiberglass pools, but some manufacturers say it is needed for the gelcoat. I don't know what is really true, so I just keep it low Truth be known, vinyl liner and fiberglass pools are likely to decline faster in a low-calcium environment. High calcium is rarely a problem If other LSI factors are adjusted properly, 500ppm calcium hardness is easily managed, without scale formation. Look at the screenshot of our LSI calculator If your pool has a vinyl or fiberglass liner, the calcium hardness level should be between 175 parts per million (ppm) and 225 ppm. If you have a concrete or plaster pool, keep the level between 200 ppm and 275 ppm

Calcium hardness and fiberglass pools - Pool Foru

The ideal range for calcium hardness in swimming pools is 150-400 ppm (parts per million), so if you try to keep your calcium hardness in the midpoint between those two limits, then you should be fine. Why raise the pool water calcium hardness level? For a swimming pool, low calcium hardness can bring trouble You definitely need calcium and a balanced saturation index if you have any exposed plaster/gunite/grout and probably if you have fiberglass with a calcium carbonate based gelcoat. You do not need it for a vinyl pool or acrylic spa. However, as noted, some hardness will prevent foaming To help prevent calcium on fibreglass pools, we suggest regularly testing the pH and calcium hardness levels in your pool water. Remember, High calcium (above 350ppm) often occurs for two reasons. First, too much calcium chloride (calcium increaser) has been added to the pool water. When this happens it often leads to calcium formation About Calcium Hardness In terms of your pool water, calcium hardness affects how soft your water feels to the touch. Ideal calcium hardness levels sit between 200 to 275 ppm, but certain states have naturally higher levels of calcium in their water. This is what makes controlling calcium hardness such an issue for some pool owners

Calcium: The Most Misunderstood Chemistry in the Pool Busines

STEP 6: Adjust Calcium Hardness. Calcium hardness is the measurement of the total amount of minerals that are found in your pool's water. If you've heard the phrase 'hard water', it is simply referring to a high mineral content. Ideally, your total hardness should fall between 200-400 ppm, however, it may vary if you have a fiberglass. Controlling Calcium Hardness in Pools. As opposed to removing calcium in pools, many pool owners opt to control the mineral build-up in pools. The primary method of control is to keep well-balanced pH and alkalinity levels. With a proper pH of 7.2-7.4 and Total Alkalinity of 80-100 ppm, high levels of calcium rarely become problematic Understanding Calcium Hardness. Reader note: An edited version of this article originally appeared in the summer 2007 issue of The Edge, a publication of the Northeast Spa & Pool Association.. Calcium hardness must be actively managed—along with pH and total alkalinity—to keep water in proper chemical balance A fiberglass swimming pool is the easiest pool to maintain due to its smooth surface, which is easy to clean and kind of resistant to algae. However, when general cleanliness and chemical levels especially Chlorine, pH, and Calcium Hardness are not maintained properly, it is easy to find organic and inorganic stains in a fiberglass pool

How to Balance the Calcium Hardness Level in Your Poo

  1. The most obvious cause of scale is often calcium. Especially in salt water pools where there needs to be a zinc anode to handle the effects of electrolysis - we often see calcium deposits form when the anode is missing. Another cause to look to for scale in pools is phosphates. The drinking water industry indicates that excessive phosphates.
  2. Optional: SC-1000 to chelate the calcium before pouring it into the pool; A dry measuring cup or bucket - dose properly. Don't cut corners. Related Procedure: How to Raise Calcium Hardness. Step 1. Test your pool water and your fill water for calcium hardness. Record results. The Orenda app will tell you exactly how much calcium chloride you need
  3. g! Calcium Hardness Control 7lb. Availability: In-Store and Online at E-Z Test Pool Supplies
  4. g pool renovation and restoration teams on Long Island. Employing only the highest quality materials in our projects
  5. e the correct amount of pool shock treatment. 30 PPM chlorine shock chart for killing algae and bacteria, and the 3.0 PPM super chlorination.

Check out my website - http://www.clean-pool-and-spa.com/calcium-hardness.htmlhttp://www.clean-pool-and-spa.com/continued-very-low-calcium-hardness-issues.ht.. Tile and Exposed Aggregate Pools - 200-400 ppm. Marcite, Fiberglass or Painted Pools - 250-400 ppm. If the calcium hardness tests less than the desired range, add this product according to the guide below. Place this product into a plastic bucket already filled with swimming pool water Regardless of physical form, neither the powder or tablet versions of calcium hypochlorite contain pool stabilizer (cyanuric acid) to protect against the sun, but instead contain calcium which raises your pools calcium hardness level over time. Cal-Hypo Quick Stats. Comes in powder (most common) or tablet form; Powder form has a pH level around. Re: Calcium hardness and fiberglass pool. If you do not have a SWG or heater, it should not be a problem. If you do, then go by the manufactures recommendations to maintain warranties. Mark. Hydraulics 101; Pump Ed 101; Pump/Pool Spreadsheets; Pump Run Time Study; DIY Acid Dosing; DIY Cover Roller. 18'x36' 20k plaster, MaxFlo SP2303VSP. Calcium Hardness. Test monthly. Calcium naturally occurs in water. Different areas of the country have higher and lower levels of calcium in the water. The higher the calcium concentration in the water, the more prone the pool is to calcium leeching. When the pH is maintained between 7.2 and 7.4 the calcium is balanced in the water

Pool Chemistry - Ordinis Best Fiberglass Pool

  1. The right calcium hardness level depends on the kind of pool you have. Vinyl or fiberglass surface must have a range of 175 parts per million (ppm) - 225 ppm, while a concrete pool must have a level kept within 200 ppm - 275 ppm
  2. g pools are winterized or even those that dip down into the 50º area, calcium hardness becomes vital. Almost every substance dissolves easier in hot water, but not calcium. Calcium dissolves easier in cold water
  3. Total hardness and calcium hardness in pool water. Scale, calcium buildup, hard water and scaling problems. content with 7.6 for to long.realistically ur levels will fluctuate but keeping it at 7.4 is ideal.if u have a liner or fiberglass then u keep it at 7.6. but if u have calcium buildup whether its leaching or scale,then u treat it with.
  4. Maintain your chlorine at or above 1 ppm and the calcium hardness at 200 to 400 ppm. If any of these numbers get out of line, stains can develop. Simply restoring balance to your pool water's universe is the easy way to prevent pool stains. Specific Fiberglass Pool Stain Strateg
  5. g pool, one of the main things that you will be concerned with would be keeping it healthy
  6. g pool water to be in balance, pH, Alkalinity, calcium hardness and Total Dissolved Solids (TDS) must be maintained in their proper range. The ranges can vary slightly, depending on the average temperature of your pool's water and the type or finish of your pool

Most experts recommend using a calcium hardness increaser, such as calcium chloride, if your water's calcium hardness levels fall below 200 or 150 ppm. If calcium hardness levels exceed 400 ppm, you can solve the problem by partially or completely draining and refilling the water. Anywhere from 200 ppm to 300 ppm is a good range to aim for For example, if your MagnaPool is running a measured calcium hardness of 200-250ppm, then your actual calcium level is too low and should be increased! MagnaPool recommends a 'total hardness' level of around 800ppm compared to 200-300ppm for typical salt pools. Calcium lumps in swimming pool Calcium Hardness refers to the amount of dissolved minerals in water. A low hardness can lead to corrosion of the pool surface, filter, heater, ladder, etc. A calcium hardness level that is too high causes cloudy water and scaling (white chalky appearance) This measures how acidic or basic your fiberglass pool water is. The pH levels need to balance at all times. The water is acidic when it has a low pH, which might corrode your pool surface. On the other hand, high pH levels may cause scaling and calcium build-up. Calcium hardness; Calcium hardness is a measure of how soft or hard the water is. 2 If the pool water becomes too soft (calcium hardness less than 150 ppm) 3 If the pool water becomes too hard (calcium hardness greater than 400 ppm) 4 First balance total alkalinity and pH. 5 Test calcium hardness, and interpret the results. 6 Adjust the calcium hardness level. 7 Conclusion

The desired range for calcium hardness is as follows: Vinyl Pools - 200-300 ppm. Tile and Exposed Aggregate Pools - 200-400 ppm. Marcite, Fiberglass or Painted Pools - 250-400 ppm. If the calcium hardness tests less than the desired range, add this product according to the guide below Calcium hardness is a concentration of calcium ions which appears in the pool water in the form of calcium carbonate. Calcium is naturally present in water, but when it comes to your swimming pool water, it needs to be maintained and prevented from going either too high or too low by keeping it within the target range of 200-300 ppm Calcium hardness in pools. The main reason that your concrete swimming pool may have a high calcium hardness is because of the concrete surface. In this case, a concrete surface will release calcium hydroxide into your pool water. However, this increase in calcium is reduced when water is removed from your pool

Fiberglass pool calcium buildup or fading gel coat and scaling trouble free my has algae rough spots how can i fix this ask the guy on fibreglass pools remove it without draining water stain remover for in your to lower hardness here s scale from balancing ground swimming spas michigan call of new inground servicing ord clarkston northville Read More Proper Pool Water Chemistry Levels Whether residential or commercial, pool or spa, gunite, vinyl, or fiberglass, the Ultimate in Pool Care's Chaikin Ultimate Pools DBA is one of the leading swimming pool renovation and restoration teams on Long Island. Employing only the highest quality materials in our projects

Understanding Swimming Pool Calcium Hardness - FROG Product

How To Raise The Calcium Hardness In Your Pool. Ah, this is the one I love!! You see, we can ALWAYS add more calcium hardness increaser to the pool to get it in the correct range of 150 - 250 ppm.. Taking out calcium hardness, well, that one is a little tricky Types of Calcium Scaling in a Swimming Pool. There are two types of calcium scaling, and one is much harder to beat than the other. Your typical, run of the mill scaling is calcium carbonate. Calcium carbonate can be a pain, but you can defeat it. The other type of calcium scaling is calcium silicate Scale (calcium carbonate) has been an ongoing problem in many pools and spas due to the fact that over time minerals precipitate (fall out of solution) and settle, becoming a solid on the surfaces. There are many different situations that can cause this process to take place, but the most common is when the water has a high calcium hardness.

Fiberglass Pool Stain Remover for Calcium Buildup in your

  1. In this video I'll explain about Calcium in your pool water; what it does, the effects of too much calcium in your pool water and what to do about it.Links t..
  2. g pool safely and efficiently? Why is it so important
  3. Calcium Hardness Increaser. If the calcium hardness is too low, the water becomes corrosive and results in the etching of the pool's surfaces. Your pool equipment, pipe fittings and pump connections could potentially corrode. As a result, the pool's walls and floor can stain. Algaecides. Algaecides prevent algae from growing
  4. Fiberglass resurfacing is an option for appearance or to correct physical issues, every 20-25 years. Fiberglass Problems: Cracks. Gelcoat is the hard ceramic like coating that covers the strands of fiberglass on the pool interior. Unlike plaster, fiberglass cracks are not caused by drying out or temperature

Total Hardness. The hardness of your water is a measure of the amount of lime dissolved in the water. Water with a calcium hardness of less than 100 ppm (mg/l) is described as soft water. Soft water can draw lime out of tile grouting and the concrete of cast pools, which can lead to disintegration Water that is too soft has low calcium hardness, which might corrode pool surfaces. Increase calcium hardness with calcium chloride, but don't add to much calcium. It can be difficult to reduce calcium levels, so aim to keep pool calcium levels between 200-400 ppm. Spa calcium hardness levels should stay within a range of 150-250 ppm

The calcium hardness should be around 250-350 parts per million (PPM). If the hardness is above 350 PPM, you will need to lower it. If the calcium levels in your pool are regularly above 350 PPM, do a calcium hardness test for your tap water Make sure you any and all of these applicable steps: Skim and vacuum your pool and thoroughly clean out your filters. Balance your chemicals as follows: pH level: 2-7.6. Alkalinity: 80-120 ppm. Chlorine residual: 0-3.0 ppm. Calcium hardness: 200 - 400 ppm. Cyanuric acid: 30-60 ppm. Metals: 0 ppm Tile & exposed aggregate pools - 200-400 ppm. Marcite, fiberglass or painted pools - 250-400 ppm. If the calcium hardness tests less than the desired range, add this product according to the guide below. Place this product into a plastic bucket already filled with swimming pool water [In fiberglass pools], most dealers keep the calcium lower, closer to 80 ppm, Schuster says. If you have 200 ppm, you close the door to using cal hypo as a shock. Using disinfectants such as cal hypo will boost calcium hardness levels, especially in areas with high temperatures and water evaporation We had a fiberglass pool installed 6 years ago and have been slowly learning how to care for it (without being at the mercy of a pool store). The poolforum has been a HUGE help in being able to maintain it properly and understand the chemicals and the equipment. One thing I have never fully understood is calcium hardness and having a fiberglass pool (with a chlorine generator)

What Maintenance Does a Fiberglass Pool Need

In your u-tube video from January, 2014, you state that the correct level for calcium hardness should be 150-250 ppm and that 250-500 ppm is too high. In a word, Why is 250-500 too high? I recently had a 20'ish year old fiberglass pool refurbished If calcium increases but was not manually added by the pool owner or operator, you know it came from the surface or tile grout. In the case of vinyl liner or fiberglass pools, low-LSI water can cause deterioration of the surface. Calcium hardness is often under-appreciated and is essential, especially in cold water Have your water tested and report back with th pH, alcalinity and calcium hardness levels. This will tell us if the problem is chemistry related or not. I've serviced a freshly resurfaced fiberglass pool this year and the problem it had (before the owner called me in) was too high a pH combined with too high alcalinity causing scaling

So now that we know that water is happy when it's balanced. What is balanced water for a fiberglass pool and how do we get it there? P.H. ~ 7.4 T.A. ~ 80 ppm. (Parts per million) Calcium hardness ~ 350 ppm. These three items that make up water chemistry can be thought of as a tripod. If one leg of the tripod is off the whole thing falls over Calcium Hardness Increasers: Like the name implies, these chemicals are designed to raise your pool's level of calcium hardness. Consider using a calcium hardness increaser, such as calcium chloride, if your measurements drop below 150 parts per million (ppm). Chlorine Neutralizers: According to the CDC, excessive chlorine can irritate your. In a liner or fiberglass pool it is harder to remove, what you would need to do is get the calcium hardness level in the pool down, either chemically or by adding fresh water, and then scrubbing (carefully - you don't want to damage the surface or scrub the pattern off of a liner) the walls and floor of the pool Calcium Hardness - The optimal calcium hardness level for plaster pools is 225 to 300 ppm and 175 to 250 ppm for vinyl, painted, and fiberglass pools. Use Calcium Plus to instantly raise calcium hardness in your pool water. Use when hardness levels fall below 150 ppm. Add Calcium Hardness Reducer when hardness levels rise above 400 ppm to.

CALCIUM (Hardness) 300 -350 parts per million. Cleaning After filling the pool, you may have some dirt or debris that has accumulated in the water. You may use your pool sweep or vacuum to clean the pool. Summary As you consider options for your pool resurfacing project, remember to consider the time and effort you will spend on startup and. Usually this means adjusting alkalinity (or if you added bicarb on fill day, you would adjust calcium hardness today). Turn on circulation system and proceed with normal startup protocol. Brushing and vacuuming should be done with tools compatible with the type of pool you have. Do not use a brush or vacuum not approved by the pool manufacturer Fiberglass pools are a great option if you're looking for a cost-efficient pool. Fiberglass inground pools require less maintenance and are easier to maintain. In this blog, we review the best way to clean a fiberglass pool and fiberglass pool maintenance. Testing for calcium hardness, cyanuric acid, and metals monthly Calcium Hardness Increaser. Calcium hardness affects how soft, or silky your water feels. Ideal range for calcium hardness is between 200 - 400 ppm. Anything higher and you'll notice a difference in the texture of your water. Each 1 lb. of Calcium Hardness Increaser will raise hardness by 8 ppm, per 10000 gallons Imperial Pool Builders address swimming pool water calcium hardness. The swimming pool service contractors from Imperial Pool Builders in Decatur, Illinois work with swimming pool owners to address the potential for calcium hardness and overall swimming pool water quality. Calcium chloride, or CaC12 is naturally occurring chemical that happens in swimming pools

Step Three: Balance Calcium Hardness. Most experts recommend using a calcium hardness increaser, such as calcium chloride, if your water's calcium hardness levels fall below 200 or 150 ppm. If calcium hardness levels exceed 400 ppm, you can solve the problem by partially or completely draining and refilling the water Calcium hardness is also very important to the chemical balancing of your vinyl liner swimming pool. Calcium for a liner pool can be a bit lower than a plaster pool, in the range of 150-250 ppm. If a vinyl liner's calcium level is too low, this soft water situation could lead to foaming and other water problems, and can harm the vinyl

Nu-Clo Calcium Hardness Increaser For Pools calcium increaser & hardnes s. Sizer 10 LB, flake granular form. 1 LB per 10,000 Gallons to Raise 15 PPM. Prevents corrosion in pools & spas. This product will raise the calcium mineral level of pool water. Maintain this level at 175 ppm (parts per million) in vinyl-lined or fiberglass pools and 240. However, because it contains calcium, cal hypo may be unsuitable for pools that already have issues with calcium hardness. Cal hypo is also unstabilized, which means it does not contain cyanuric acid (CYA), a chemical that helps to shield free chlorine from ultraviolet (UV) rays emitted by the sun

Below is a list of our recommended water balances: pH 7.2 - 7.8 (7.0 - 7.2 in fiberglass pools) Alkalinity 80-120ppm. Calcium hardness 200-250ppm (Concrete) Calcium hardness 175-225ppm (Vinyl) Free Chlorine 1-3ppm. Effective sanitising relies on pH values. Therefore, sanitiser and pH levels should be the measures you check and adjust most. Reduce hardness in pool water. As with every other aspect of water chemistry, calcium hardness also needs to be in balance to protect your pool surface from calcium formation, stains, or corrosion. Unlike pH and chlorine, the calcium level in most pools does not vary greatly over the seasons, so testing every few months is normally enough Calcium Hardness: 175 - 225 ppm (Vinyl Pools, Above Ground Pools, Fiberglass Pools, Swim Spas ) Free Chlorine: 1 - 3 ppm: Free Bromine: 3 -5 ppm: Metals: Copper: 0 ppm: Metals: Iron: 0 ppm: What is pH and how does it affect my pool water? pH is the measure of acid and base in the pool water. The pH of the pool should be tested and adjusted, if. Lowering the Calcium. The first thing you'll want to do is remove calcium from pool water. For this, you'll need to partially drain your pool. The optimal calcium level is 200-400 ppm. A higher ppm causes deposits on the surface and cloudy water. Then refill the pool adjusting the alkalinity The calcium hardness should be around 250-350 parts per million (PPM). If the hardness is above 350 PPM, you'll need to lower it. Some areas have very high levels of calcium in the public water supply, which causes higher calcium levels in your pool. Say calcium levels in your pool water are routinely higher than 350 PPM

What to do with your pool while you are on Vacation

Pool Water Chemistry - Pool Calcium Hardness & Maintenanc

An acceptable hardness level for plaster pools is from 225 to 300 ppm and 175 to 250 ppm for vinyl, painted, and fiberglass pools. Low levels of calcium create corrosive water which can damage equipment. Raise hardness levels by using calcium boosters. Lower hardness levels by using calcium hardness reducers Your fiberglass pool is designed to remain full of water at all times, as most pools are. Only drain any in ground pool with the supervision of a pool professional. Your test kit should be able to test PH, total alkalinity, calcium hardness and sanitizer level. The kit should include a cyanuric acid test for chlorine sanitized water. The. Carbonate Scale is a buildup of hardened calcium carbonate (CaCO 3) on pool surfaces or equipment.Scale can be a big problem for a pool and its plumbing system (and other water systems besides pools, like fountains). Like most of our articles on the Orenda blog, this article is meant to simplify chemistry so that the chemistry can be better understood Secondly, you need to balance alkalinity. The ideal alkalinity in a fibreglass pool is 80-120ppm. To raise alkalinity, use a buffer like Sodium Bicarbonate. Finally, you will also need to adjust the calcium hardness. A pool with low calcium will cause corrosion to the equipment while very high amounts may deposit on the surface For most hot tubs, the appropriate levels are: pH balance: 7.2-7.8. Alkalinity: 80-120 ppm. Chlorine: 1.5-3.0 ppm (or) Bromine: 3.0-5.0 ppm. Calcium Hardness: 80-200 ppm. So, let's take a look at this a little more in depth to help you understand how to measure the calcium hardness level and adjust it when needed

Lowering Pool Calcium Hardnes

Are you sure you're looking at scale?https://blog.orendatech.com/opening-a-pool-with-crystalsEspecially in colder climates, people often mistake underwater c.. Is Your Calcium Hardness Too High? Calcium hardness is a measure of how much calcium is in the water, with the recommended range being somewhere between 200 ppm to 400 ppm. While low calcium hardness levels can cause damage to your pool fittings, it's the opposite side of the spectrum you need to be concerned with here Hi Karen, total or calcium hardness will not make your pool appear cloudy. Calcium hardness of 250-350 ppm is needed mainly to protect pool parts such as tiles, plaster, or concrete from corroding. If your chemicals especially chlorine reading is ok, you can try vacuuming the pool if that will help

Raising Pool Calcium Hardnes

S. Mithra Fiberglass swimming pools are sometimes a better choice than concrete for backyard pools. For people who plan on living in a home and using an in-ground swimming pool for a long time, fiberglass swimming pools are often a better value than poured concrete pools. Although the prefabricated fiberglass material is more expensive than concrete or vinyl liners in upfront installation. Reducing Pool Calcium Hardness Levels Place the filter system on Recirculate or remove filter media. Raise the pH to 10.0 by adding ph Increaser. Circulate pool for 8-12 hours, water should be cloudy, retest pH using diluted sample* Water Hardness Increaser helps bring calcium levels to their ideal range of 150-200ppm for vinyl or fiberglass pools or 200-400ppm for concrete or plastered surfaces. The right water hardness prevents the corrosion of pool equipment and staining of surfaces, keeping your pool looking its best Adjust calcium hardness to 200-275 ppm for plaster pools, 175-225 ppm for vinyl or fiberglass pools by adding Calcium Hardness Increaser. Be sure to follow label directions. • Check the free available chlorine level and adjust to 1-4 ppm by adding a granular chlorinating product Calcium hardness. For vinyl pools, calcium should be between 150-250 ppm. A low level can result in foaming, which is unpleasant but shouldn't harm the liner. If calcium hardness goes above 400 ppm, you will likely see a white, flaky crust on the liner and pool equipment. It also produces itchy skin

Pin on Pools Professor

Calcium Hardness ? - Swimming Pool Hel

Get prescription strength clarith with the Rx Clear Calcium Hardness Increaser! Use when the calcium hardness reading in your pool drops below 150ppm and this product will increase calcium hardness in water to prevent any stains or deterioration. The ideal range is 200 to 400 parts per million (ppm). Six lbs. per 10,000 gallons will raise the. Current selection is: 25 lbs. <p>Get prescription strength clarith with the Rx Clear Calcium Hardness Increaser! Use when the calcium hardness reading in your pool drops below 150ppm and this product will increase calcium hardness in water to prevent any stains or deterioration. The ideal range is 200 to 400 parts per million (ppm) What Is Calcium Pool Scale? Calcium pool scale is a chalky-looking film of calcium deposits that build up on your pool finish if your chemistry levels or pH balance is out of whack, or you have an abundance of calcium (high calcium hardness) in the water.. An increase in calcium hardness levels can occur after adding it to the water, or the water taking it from anywhere it can find it (usually. Stabilized chlorine already has a base pool conditioner added. Calcium Hardness Increasers: If your calcium hardness level is too low, known as soft water, it can corrode pool surfaces. Increase calcium hardness levels with calcium chloride, but don't add too much because calcium levels can be hard to reduce

Fiberglass Pool Stain Remover for Calcium Buildup in yourCalcium on Fibreglass

Increases calcium hardness levels in pool water. Proper calcium levels protects pool surfaces and equipment. Features Raises calcium hardness Pure flakes minimize clouding in pool water Benefits Prevents long term damage to vital pool components Easy to use application Applications In vinyl and fiberglass pools, calcium hardness levels should be between 150 - 250 ppm In pools with plaster or. Fiberglass and vinyl-liner pools are in the more affordable range, while a custom concrete pool can cost well beyond this higher range of $60,000. Depending on the region of the country where you live, an average fiberglass pool's initial cost of installation is approximately $35,000 - $40,000. If you factor in the yearly maintenance cost. Keep a clean pool to keep organic waste levels to a minimum. Bio-matter in the pool, including algae, coagulates to form dirty stains, especially during scaling events. Regularly test pool water and keep it balanced with proper pH, alkalinity and calcium hardness levels. Also check for the presence of metals in the water