Lesson 8 - Prevention

    Preventing a problem before it occurs is always preferable to dealing with one after it rears its ugly head. We all know this lesson and have applied it to many aspects of our lives. Pools are no different in this regard.

    Yet knowing that prevention works and preventing bad things from happening are worlds apart. After all, how many of us can 1) accurately predict that a problem is coming, then 2) properly analyze what will need to occur to head off disaster, and finally 3) have the foresight to take the correct action at the proper time to effect full fledged prevention? As many years as I've been maintaining pools, I must admit that sometimes swimming pools surprise the heck out of me. 

    Thus prevention in the abstract is always desirable, but as a practical matter it's not as easy to carry out. Despite the obvious difficulties involved, prevention of many of the problems you will face as a pool owner is possible. As your experience level grows, so will your predictive ability. And making correct predictions is half the battle. Some lessons you will no doubt learn the hard way. But if you have a sharp mentor, you can avoid some of the most obvious pitfalls.

    We can only move to prevent what we can anticipate in advance, and then only those things that are indeed preventable. So it might be useful to make a list of things you can prevent, and things you cannot prevent. I am reminded of the Serenity Prayer - it goes something like this: "God grant me the serenity to accept the things I cannot change, the courage to change the things I can, and the wisdom to know the difference." 

    When deciding whether or not to take a particular preventive measure, the likelihood of an event occurring must be weighed. In the above lists, some of these things will certainly happen to your pool (motor failure), some will certainly not happen (winter freeze in San Diego, and some will depend entirely upon you (accidents). Most of the non-preventable things can be slowed down, be they are virtually inevitable (resurfacing).

    Here's a catch. If you take a preventative measure and nothing happens (good or bad) how would you know if you prevented something, or it just didn't happen because it was never going to happen in the first place?

    The answer is to weigh the likelihood of an event occurring against the cost (or perhaps even the risk) of trying to prevent something. Algae is a perfect example. Many pools in Memphis have an episode of yellow algae (called mustard algae) growing on the shady walls of the pool in late July or August. Not every pool will get it, nor will it happen every year.

    Now, you can sit back and wait to see if you get the yellow algae this year in your pool. If it does, then you can treat it at that time. Or, you can try to anticipate it and add mustard algaecide in mid-July to head it off. Which would you do? 

    I suppose it partly depends on the kind of person you are. If it were my pool I'd ask myself a series of questions. How often has my pool been afflicted in past years? (That addresses the likelihood question.) If my pool has had it every year for the past five years, then it's a good bet it will be back again this year. In that case I'd try to prevent it. However, if my pool had it ten years ago, and not since, I'd wait and see. 

    But what if my pool seems to get it every once in a while?  Then I need to ask myself about the risks of getting it wrong? If I add algaecide and it turns out I don't need to, I'm out maybe $20. If I wait until the algae appears, I'm still out the $20, but I have to brush the pool too. (Brushing is OK though because I need the exercise.)  Since the cost is about the same either way, as I said earlier, it may come down to what kind of personality you possess. 

    Suppose that once the algae has a foothold it spreads rapidly and is hard (or impossible) to get rid of. Black algae is often like that. Then the case for prevention would be much stronger. Yellow algae presents a more ambiguous choice since it is easy to get rid of. What about green algae? 

    Green algae is easy to get, not always easy to get rid of, but sometimes goes away quickly. Should you try to prevent it? I'd say yes, always. But I wouldn't use algaecide. Normal chlorine levels are enough to prevent green algae. So if you are doing your job disinfecting the water, green algae will usually stay away. Plus, by chlorinating to prevent green algae, you will be preventing black algae as well. 

    Yellow algae is a different story, though. It is not afraid of chlorine, so mustard algaecide is the only way to prevent it, and to treat it once it takes hold. But I would not recommend adding algaecide every week to prevent something that only occurs once a year.

    Let's apply what we've learned to other prevention matters. In Lesson 3 - The Water, I talked a bit about dissolved metal in the water. Now I want to discuss how to (and whether to) prevent metal stains in your pool. 

    Metal stains can show up as discoloration on the pool surfaces. They may be brown, green, blue, rust or some other color. If you never experienced a problem with metal stains before, I certainly would not advise going out and buying a stain preventative now. Wait until you notice a discoloration before treating a metal problem. Basic rule: don't try to treat a problem you don't have.

    If you should happen to see some discoloration then the first step is to have your water tested for metal content. If the results show that you have a higher than normal metal content, then a stain treatment may be in order. But here's a twist. You can have so much metal in the water that it cannot be prevented from staining your pool. In other words, there is a limit to prevention. When this occurs, the only solution is to take water out of your pool and replace it with fresh water with less dissolved metal in it.

    Let's see what happens when we apply prevention to motor and pump failures. Such problems are listed above in the "Non-preventable category" because they are inevitable. Yet you can influence how long it will take for the inevitable to occur. Assuming that the pump and motor you have are not lemons from the factory, they will have a certain lifetime. Depending on the quality of the pump, it may last anywhere from 4 years to 8 years. I have seen them last 12 years and even longer. But eventually every pump wears out and has to be replaced.

    Is there anything you can do to prevent the pump from failing? No. Can you take actions that will prolong the life of the pump? Yes. So in a sense that's a form of prevention we call preventive maintenance. Some pool stores sell plastic motor covers that protect the motor against sunlight beating down on the motor. Less heat = longer life. Also you can build a room over your pool equipment, again to protect against the elements. Indoor systems tend to last longer than outdoor systems. At the very least I would recommend covering your pool equipment if you winterize your pool and shut it down for the winter.

    Some people ask me if running the pool only 12 hours a day instead of 24 hours will prolong the life of the pump and motor. In other words, will your pump and equipment last longer if you put it on a timer? That is an interesting question which can be answered several ways. First, pool equipment is designed to run continuously. It doesn't hurt the equipment to run all the time. In fact, motors rarely quit while they are running. Usually they fail to come back on after they have been turned off. 

    Second, turning a pool motor off and on can, in theory at least, shorten its working life. Consider two examples. If you stood at a light switch and turned a light off and on repeatedly, it would burn out after a relatively short period of time. By doing this you are heating up the filament, letting it cool down, then heating it up again. Think of bending a coat hanger over and over until it breaks. If you want to get the full amount of life out of a light bulb, leave it on continuously.

    Another example. When I bought my first computer I thought I was smart to turn if off every time I finished using it. People told me it was best to leave it on all the time but that seemed wasteful to me. So I was turning my computer off and on two or three times a day. After about 8 months, my hard drive started slipping. The mechanism that made the disk spin was not engaging properly. After replacing the hard drive I tried leaving it on all the time, turning it off only to reboot. That was 5 years ago, and the hard drive is still humming away.

    I don't know for sure, but I think pool motors are the same as hard drives and light bulbs. They will last longer if they run continuously. And like coat hangers, you shouldn't bend them repeatedly either.

    Seriously though, here's another way to look at the debate of whether to put your pool on a timer or not. When your pool is off, it is vulnerable. It's not filtering, it's not skimming, no chlorine is being added. It is defenseless. Think of a glass of water sitting outside. As we learned in Lesson 5 - Disinfection and in Lesson 6 - Filtration, water will go downhill quickly without human intervention. If you feel you must turn your pool off during some portion of the time, at least turn it off at night when the pressures on the pool are less (less wind, sunlight and heat).

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