50 Causes of Swimming Pool Algae

dog-days-of-summer-2Currently, the Dog Days of Summer Sale is running here at In The Swim, which reminds me of an old phrase – the “algae days of summer“.

It’s the time of year algae has been waiting for. As water temperatures soar into the 80′s, your sanitizer struggles to keep up – ideal conditions for algae.

But there are other causes of swimming pool algae. So many in fact, that I’ve curated a list of what causes algae to grow in pools. In most cases, it’s not just one factor, but a combination of many…

What Causes Pool Algae?

Water Chemistry Problems

  1. Low free chlorine levels, below 1.0 ppm
  2. High combined chlorine levels, above 0.3 ppm
  3. High pH levels, rising above 7.6
  4. Low calcium levels, below 150 ppm
  5. Low alkalinity levels, below 70 ppm
  6. Low cyanuric acid levels, below 20 ppm
  7. High cyanuric acid levels, above 100 ppm
  8. Very high total dissolved solids, over 10000 ppm
  9. Never brushing your pool; ≈ weekly
  10. Never diluting the water; ≈ annually
  11. Not shocking the pool enough; ≈ monthly
  12. Not testing and balancing the water enough; ≈ weekly

    Pool Water Contamination

  13. Dead remains of previous algae blooms
  14. High levels of dissolved carbon dioxide
  15. High levels of nitrates or nitrites
  16. High levels of phosphates
  17. High levels of bacteria
  18. High levels of ammonia
  19. Dirty pool, lots of leaves, debris
  20. Heavy swimmer use, bodily wastes
  21. Mulch leaking in or blowing into pool
  22. Fertilizers carried in from rain or wind
  23. Run-off from nearby lawn or planters
  24. Sap and pollen from overhanging trees
  25. Urban pollution from cars and planes

    Equipment Problems

  26. Pump is overheating and cycling on/off
  27. Pump is too large for the pool filter
  28. Pump impeller is clogged or broken
  29. Leaking or low water levels, drawing air
  30. Stuck skimmer weirs, drawing air
  31. Air leak before pump, drawing air
  32. Poor circulation in a large pool
  33. Filter is too small for pool size or pump
  34. Filter cartridge not seated properly, or missing parts
  35. Filter cartridge or sand needs replacement
  36. Filter not running long enough daily
  37. Multiport valve is recirculating or bypassing filter
  38. Suction or return valves are closed
  39. Salt chlorinator cell needs cleaning
  40. Salt chlorinator cell needs replacement
  41. Salt level in pool is too low
  42. Tablet chlorinator is clogged
  43. Tablet chlorinator is air locked

    Other Problems…

  44. Rough concrete pool surfaces
  45. Gravel, plants or fish (!) in the pool
  46. High water temperature, over 80° F
  47. All day sun exposure, over 8 hrs daily
  48. History of persistent algae every spring and summer
  49. Dogs, ducks or other animals using the pool regularly
  50. Non-pool items in pool; furniture, bicycles, skateboards, shoes, fruit…

pug-in-poolIt’s often not just one thing that causes pool algae to bloom, but a combination of factors that come into play.

To sum it all up, keep your water balanced and sanitized, make sure your filtration and circulation is optimal, and keep contaminants away from your pool.

Davy Merino
InTheSwim Blog Editor


Alzheimer’s Disease and Swimming


Welcome back and let me thank you for joining another one of our discussions on health and aging. I’m Dr. Pool, and our talk today covers Alzheimer’s disease.

Alzheimer’s is a growing problem for the population as a whole, and there is no known cure. However, there are things that can be done to strengthen your body and improve your balance. Exercise and more specifically, swimming is just one such example.

To begin, allow me to provide a framework for the discussion on Alzheimer’s Disease.

  1. What is Alzheimer’s Disease? 
  2. Symptoms and Treatment
  3. Swimming with Alzheimer’s

bluecrossWhat is Alzheimer’s?

Alzheimer’s is an irreversible brain disease that deteriorates thinking skills and memory. While it is most prevalent in ages 60 or over, it can also affect those in their 50s and in rare instances, even younger.

It is the most common cause for dementia in adults – dementia is a loss of memory and intellect and not considered a disease. Dementia is a group of symptoms that may or may not accompany other diseases. It can affect the brain in other ways, in addition to the memory loss, including loss of judgment, confusion, and personality changes. Alzheimer’s can be found in 50 to 80 percent of dementia instances.

Those who have Alzheimer’s have memory problems and difficulty with reasoning and thinking, which leads to the inability to live independently. Changes that occur in someone suffering from Alzheimer’s can create a great deal of difficulty for them as well as their caregiver.

Because Alzheimer’s gets worse over time, it is known as a progressive disease. Symptoms develop slowly and become worse with time and eventually get severe enough to impede daily tasks. Alzheimer’s disease causes cells to die, bringing irreversible damage to the brain.

Although research continues, Alzheimer’s remains without any known cure. It is the sixth leading cause of death in the United States.

It is estimated that over 5 million Americans of many ages have Alzheimer’s in 2013, and the likelihood of developing Alzheimer’s double every five years after age of 65. After the age of 85, the risk reaches nearly 50 percent.


bluecrossSymptoms and Treatment

The most common symptom of Alzheimer’s is forgetting new information. Because Alzheimer’s affects the part of the brain which deals with learning and retaining new information, sufferers lose short term memory. As it worsens, it begins to affect long term memory, mood and behavior as well as presenting challenges in walking and speaking.

Those who may be suffering from memory loss or other potential signs of Alzheimer’s can find it difficult to confirm if they indeed have the disease, although it may appear more obvious to family members.

While there is no treatment for a cure, there are treatments that can slow dementia symptoms and improve the quality of life, meanwhile the search continues for ways to treat and someday prevent Alzheimer’s from occurring.

There are medications that can lessen the impact of symptoms for limited time periods. The FDA has approved two medications – Memantine – which includes Namenda, and Cholinesterase inhibitors – such as Aricept, Exelon, Razadyne and Cognex. These medications are used to treat the cognitive symptoms such as memory loss and confusion – but they are not permanent solutions.

Doctors may also recommend high doses of Vitamin E, a balanced diet and safe forms of exercise – like swimming!


bluecrossSwimming with Alzheimer’s

In general, physical activity is good for those suffering with Alzheimer’s – it gives them something to do while keeping their body occupied and staying in shape. Alzheimer patients are not a high risk for drowning, but should be supervised or assisted during water exercises.

As mentioned above, there is no known cure for Alzheimer’s. Bearing this in mind, regular physical activity can improve the health and well being of most people, and there are additional benefits when it takes place in water.

Studies show that exercising in a pool improves muscle strength and cardiac and respiratory health, improves mood and reduces anxiety. Additionally, a new study shows that women who were involved with a six-month water exercise program had increased their strength and suffered less falls, as compared to land based exercises.

Most of those diagnosed with Alzheimer’s are elderly, and falls can be a concern because of brittle bones. Perhaps the main benefit to swimming or water exercise is the buoyancy of the water.

Another benefit to water exercise is that although you feel 8x lighter in the water, the resistance to movement amplifies the workout. Moving slower through water than air, the resistance increases the effects of the workout, without requiring a correspondingly increased respiration or heart rate.

Though water exercise will not halt the progression of Alzheimer’s, it can be good for the body and mind by adding fitness to the daily routine. Swimming or water exercise can also improve the mental well-being, and provide a social outlet.

Dr. Pool

Dr. Pool


"Home Safety for People with Alzheimer's Disease." National Institute on Aging. 12 Oct. 2011. Web.
 "What Is Alzheimer's?" Alzheimer's Association. Web.
“Medications for Memory Loss” Alzheimer’s Association. Web.
"Water Exercise for Alzheimer's." Endless Pools. Web.
"Pool Exercise May Build Strength, Reduce Falls." Pool Exercise May Build Strength, Reduce Falls. Dementia Today, 25 Apr. 2013. Web.


Shopping 100+ Swimming Pool Lounges

dreamstime_xs_37442927-gif-100-plus-pool-floats-2The summer heat is blazing, the pool water is warm, it’s the perfect time of year to relax in a pool float or lounger.

So, when my InTheSwim catalog came in the mail, it got me thinking that I need to buy a new pool float for summer!

Easier said than done, we have over 100 floating pool lounges to choose from – how did I narrow down the choice, and choose just one?

Here’s how I did it…

PRICE: I had to consider price, first and foremost. Of the 100+ pool floats, there are prices between $9 and $369 ~ so I needed to narrow the range. I decided to buy a really good pool float this year, so I gave myself a budget of $200.

TYPE: To make it easier, I split up the floats into 3 distinct types of pool loungers, and chose two of the best pool floats from each category that were in my price range.

I.    Inflatable pool lounges
II.   Foam chairs and lounges
III.  Pontoon type sling lounges


Now, I’ve had inflatable pool rafts before, and most of them don’t last a season or two, but we have some really nice inflatable pool floats, so I included two of them into my list for consideration.

Body Glove Dual Lounger

Price: $105   Type: Inflatable


Body Glove Lounger

With almost 25 square feet of surface area, this float is huge! Gonna need a big air pump for this one! (ugh).

The best features are the soft combed top surface, and it’s jumbo 66″x91″ size. This big float that will keep you (and a friend) high and dry.

AquaSofa Floating Lounger

Price: $125   Type: Inflatable


AquaSofa Lounger

Another pool float with room to share, the AquaSofa measures 68″ round, and 36″ tall. Comes with matching sofa cushions, carry bag and air pump!

Soft covered vinyl is very comfortable, and raised edge keeps you dry. Great for snuggling!


Foam pool chairs and loungers are made with a very dense, closed cell foam – virtually unsinkable! Foam chairs are lightweight, never need air, and are very durable, too.

Aquaria Aqua Hammock

Price: $105   Type: Foam


Aquaria Aqua Hammock

The Aqua Hammock is made with color saturated Aqua Cell foam, and unlike other foam floats with a vinyl coating, will not peel, chip or fade.

49×26″ is the perfect size for me, it’s easy to carry and always ready to go. Guaranteed never to sink!

Luxe Sunsation Foam Lounger

Price: $195   Type: Foam


Luxe Sunsation

You’ve probably heard of the ‘World’s Thickest Pool Float’ – it’s 2-1/2 thick vinyl coated closed-cell foam, with built in headrest.

You’ll still get wet with this, unless you weigh 98 lbs, but it gives the most floatation of all the classic style foam pool floats. 72″x26″ size.



That’s what I call them anyway – those type of sling back chairs, with two air filled plastic pontoons for support. Lightweight, durable, and very comfortable, with adjustable back positions.

SunChaser EvaFloat

Price: $160   Type: Pontoon


SunChaser EvaFloat

I’m looking for something a little different, and the EvaFloat combines a high density foam seating area, with two streamlined pontoons.

Frame made of super strong tubes of rolled resin; will never bend, rust or warp. Keeps you mostly above the water, in a comfy upright position. 50″x32″ size.

SunChaser SunSoft Lounger

Price: $150   Type: Pontoon


SunChaser SunSoft

I think you can see what appeals to me about this float. Super thick padding gives this pool float extra points for comfy-ness!

Made of fast drying mesh fabric and filled with fast drying spun polyester, mated with the SunChaser streamlined pontoons and heavy-duty rolled frame.


Now I had it down to a list of six cool pool floats, and I was still having trouble deciding, so you know what I did? I bought them all!

Just kidding, but I did buy two, and have been very happily enjoying my Body Glove Dual Lounger and the Aqua Hammock.

It was only $11 to ship them to my house, and with a 10% Off coupon I found online ;-) , I got not one, but two pool floats, with my $200 budget.

Avoid the confusion of over 100 pool floats and loungers. and just choose one of these above for your pool!100-pool-floats

And now, I must return to the pool, to float away the day…

Ida Gonzalez
InTheSwim Staff Blogger


Pool Stain Wars – Know your Enemy!

pool-stain-chart, image purch from dreamstime

The pool stain battles are fought every day in backyards across America. Stains have appeared in all pool types, plaster, vinyl or fiberglass, marring the beauty of pool surfaces, steps, rails and underwater lights.

If your swimming pool has stains or deposits, and these concern you, I understand, and feel your pain. I am also a stain-o-phobe.

Pool Stains – Intelligence

To defeat pool stains, a battle plan must begin with good intelligence. If you can identify the source of the stain, their weaknesses can be better exploited.

Colors: Identification by color is a useful classification.

red-stains - image purch'd thru dreamstime

RED: rust stains, berry stains, iron staining

brown-stain - image purch'd thru dreamstime

BROWN: dirt, leaf or worm stains, dirty scale deposits

teal-stain - image purch'd thru dreamstimeTEAL: staining from copper algaecides or copper heater

blue-stain-2BLUE: or purple stains could be manganese or cobalt, or berries


GREEN: or yellow stains can be algae, or other organic stains

Occupied Region:
Where have the rebel stains infiltrated? Is the stain an all-over discoloration, or are the stains concentrated in isolated areas? All over staining can be almost anything, but isolated stains could help pinpoint the source.toy-soldiers

Just around the main drain for example, is usually an organic stain. Isolated spots could be rust stains, or the beginning of an algae bloom.

Strength of Forces: Assess the strength of the stains by brushing it vigorously with a steel bristled pool brush (plaster pools only), or a nylon pool brush. A stain with a texture, or a scaly surface indicates a mineral deposit, possibly mixed with other [colored] contaminants.

Reconnaissance: Once you have cornered the enemy, conduct some tests to determine their weakness. Before you begin, balance the pool water, making sure your levels are correct for chlorine, pH, alkalinity and calcium hardness.

army-man-2Use Granular Chlorine (plaster pools only), in a small area to test for stain removal. If successful, you have an organic stain (algae, leaf tannins, worm stains).

army-man-2Use Vitamin C (ascorbic acid) in a small area to test for stain removal. If successful, you likely have a metal stain (copper, iron, manganese).

army-man-2Use a PoolStone cleaning brush (plaster pools only) to test for scale and stain removal. If successful, stains are only on the surface, and not soaked in.

Jack’s Magic Stain ID Kit

jacks-magic-stain-ID-kitIf you want a better way to identify the source of the stain, buy the Stain ID Kit. Balance the water, and follow directions, using 4 topical tests to help you choose the best Jack’s Magic stain removal product.

Pool Stains – Plan of Attack

Once you have balanced the water and done some tests to determine the type of pool stain you have, you can plan your attack. mineral-stain-treatments

Metal stains respond to stain removal chemicals like those pictured to the right, which can also work well on organic stains.

Iron and Copper stains can be the most difficult to remove, and mineral scaling mixed with dirt is also tough for removal chemicals. For extreme scaling and staining issues, draining and pressure washing or acid washing (plaster pools only) works well.

For areas with air quality problems, or lots of oiled-up swimmers, use an enzyme to launch a counter attack – before they stain!

vinyl-pool-stain-prevention-chemicalsIn The Swim has a full line of stain removal chemicals, in addition to sequestering agents to keep minerals and metals tied-up in solution, where they can’t stain your pool.

~ Keep your water balanced and your pool clean and chlorinated and stains are less likely to form.

At ease, soldier!

Davy Merino
InTheSwim Blog Editor


Stroke Recovery with Pool Exercise

drpool-med-bookHello again, Dr. Pool here, Chief Evangelist for water exercise as the most useful form of physical activity. Practical too, if you are already a pool owner.

Suffering a stroke can be debilitating and traumatizing. It can cause injury and damage to both the body and the brain.

There are treatments that can help prevent and treat the after effects of a stroke. One such treatment for stroke victims is aquatic exercise. Simple movements and exercises done in chest deep water.

As per our usual format, we begin with an outline for the discussion on Stroke Recovery:

  1. Stroke – Background
  2. Symptoms and Prevention    
  3. Exercise and Swimming

bluecrossStroke Background Information

A stroke is known to be caused most commonly from a blood clot that forms in the brain artery. Treatment can vary from a medicines to dissolve the blood clot to medications that reduce some risk factors for strokes in the future.

Rehab is an important treatment factor as well. Disability can occur as a result of a stroke depending on the area of the brain that is most affected and how quickly treatment was given.

When a stroke occurs, it cuts off the blood supply to part of the brain. The brain needs constant supply of oxygen, contained in the blood. When the blood supply is cut off, the cells in the affected areas of the brain slowly die. Strokes are sometimes referred to as a brain attack.

The blood supply for the brain is delivered by four main arteries. These are the right and left carotid arteries and the right and left vertebrobasilar arteries. These branch into smaller arteries that supply blood to all of the areas of the brain.

The area of the brain and the extent of stroke damage depends upon which blood vessel was affected in the first place. If blood supply is lost from a main carotid artery, a larger area of the brain is affected – which in turn causes severe symptoms or even death. If a smaller branch artery is affected then only a small part of the brain gets damaged, which in comparison can have relatively minor symptoms.

What are the different types of strokes? There is the Ischemic Stroke, and the hemorrhagic stroke. In some cases there are also cases of stroke that occur from an unknown cause.

The Ischemic stroke is a condition caused from blood clot(s), as described above. It is the state of reduced blood and oxygen supply in part of the body. This occurs in 70% of all stroke cases. Blood clots usually form from pieces of fatty material known as atheroma, or arterial plaque. Atheroma patches form on the inside of arteries in many older people, and can flake off to form a blood clot.

In a hemorrhagic stroke, a damaged or weak artery can burst and bleed. The blood spills into nearby brain tissue, causing brain cells to lose oxygen and die. This occurs in 1 in 10 strokes, or 10%.

The subarachnoid hemorrhage occurs when a blood vessel bursts in the subarachnoid space, which is the narrow area between the brain and skull. It normally is filled with a cerebrospinal fluid. It is estimated that 5% strokes are due to this subarachnoid hemorrhage.

bluecrossStroke Symptoms and Prevention

Stroke Symptoms. These vary depending on what area of the brain was affected in particular. Symptoms can develop suddenly, including arm or leg weakness, ranging from paralysis of one side of the body to a mild clumsiness in one hand; a weakness and twisting of one side of the face, causing saliva to drool down; problems with coordination, vision, speech and balance; dizziness, confusion or headache. Loss of consciousness while rare, does happen in extreme cases.

If you believe you may be having or have had a stroke – get to the hospital right away, a brain scan is essential, to define the type of stroke you have had – ischemic or hemorrhagic stroke. Treatment for these two can vary, which creates an urgency for a quick and accurate diagnosis.

Stroke Prevention. There are several factors that can be attributed to helping to prevent strokes. Risk factors can increase the chances of atheroma forming on the lining of the artery, which increases the chances of suffering a stroke. These factors include smoking, alcohol, high blood pressure, body weight, cholesterol level, diet, and activity level.

Chemicals in tobacco are known to damage and restrict arteries. Kicking the habit cuts the risk of having a stroke.

High blood pressure can likewise cause arterial damage. Treating high blood pressure has an profound effect on reducing the risk of having a stroke.

Simply losing weight is also recommended for reducing stroke risk. Physical activity should be regular, several days of the week. Just 30 minutes weekly is helpful for reducing stroke risk.

Cutting down on alcohol and consuming a healthy diet can also help bring down the risk. A healthy diet should have fruit and vegetables daily and include regular portions of fish. Finally, limit the amount of salt intake in your diet.

bluecrossStrokes and Swimming

Being proactive with prevention by activity and diet can be a great way to prevent a stroke in the first place. Exercise can also be helpful to the road to recovery, but what kinds of exercise is the most advantageous in this situation?

Studies have shown that regular aerobic activity that improves cardiovascular fitness and health after a stroke is consistent with that of recent consensus statements on exercise for able-bodied individuals. Many studies show a connection between paretic knee-extension torque and locomotion ability and  walking speed after a stroke.

A common occurrence after a stroke is experienced is muscle weakness and feeling a loss of limb control. Survivors of strokes work with therapists to regain the strength and control via targeted exercises. Exercises that are recommended include stretching, walking, bending and swimming. If the pool is accessible and there is a helper available, it would be safe to exercise in the pool.

The National Stroke Association actually states the swimming is one of the best exercises you can get for post-stroke patients. The water is a safe place to practice activities like walking. You can also improve balance while gaining a cardiovascular workout in the water.

Water is low-impact and that is easy on the joints and bones as opposed to the movement on land.

Get your Swim On, America!
Dr. Pool

Dr. Pool


"Stroke Health Patient.co.uk" Patient.co.uk. N.p., n.d. Web. 14 May 2014.
"Physical Activity and Exercise Recommendations for Stroke Survivors." Physical Activity and Exercise Recommendations for Stroke Survivors. N.p., n.d. Web. 14 May 2014.
"Celebrating30 Years." National Stroke Association. Http://www.stroke.org/site/DocServer/hope4.pdf?docID=524, n.d. Web. 14 May 2014.
"Post-Stroke Exercises." LIVESTRONG.COM. LIVESTRONG.COM, 21 Oct. 2013. Web. 13 May 2014.