Pool Care Updates

Sunday, April 21st, 1996

The Latest Research on Bioslimes

by Dennis DiPaolo

Two years ago we reported on a growing pool water problem here in the Northeast—bioslimes. Frankly, the problem has grown more pronounced in the past two years, and is now prevalent east of the Mississippi river and throughout the south.

The industry’s two largest swimming pool water research labs (Biolab and Baquacil) have spent well into six figures trying to learn how to prevent bioslimes and how to cure them. We expect to see official recommendations in time for the 1997 swimming season. However, I am often consulted by one of the labs for input on how to turn lab results into real-life solutions. I have a pretty good idea where the research is headed. In fact, some of our customers this year will be participating in a research program for Baquacil that will very likely be offered to the general public next year.

First, Some Background:

What’s the Problem?

Bioslime is a generic term for various growths that protect themselves from environmental predators by secreting a polysaccharide coating around themselves. The coating feels slippery to the touch—hence the name. The actual growths may be bacterial or fungal, but we don’t know of any that are actually algal—though our customers always seem to think they are an algae. In color, we’re used to seeing them as white, gray, clear, or pink.

These organisms often grow well in the dark. They are common in bathrooms (pink slippery stuff along tile grout), in birdbaths, inside oil wells and oil pipelines, and inside medical catheters.

Since the polysaccharide coating protects the actual organism from normal doses of chemicals (including poisons) they are very difficult to kill.

From around 1988 to 1992, water molds (a white or gray bioslime) became an annoying problem to a fortunately small number of swimming pools. Since 1993, complaints of water mold have been lower each year. However, the incidence of pink slime seems to be on the rise.

Frankly, swimming pools are much like people. Some are always healthy. Some are always sickly. Generally (but not always), people who diet and exercise are healthier than those who do not. Well-maintained pools usually do not catch “diseases” (algae, cloudy water, bioslimes, etc.). However, it can happen to anyone.

Also, there are periods (outbreaks) when some diseases are common (Hong Kong Flu, Asian Flu, measles, etc.) and then they become less so. It’s the same with swimming pool “diseases”. Some years there’s lots of mustard algae, or black algae, or cloudy water. After two or three years of problems, they just go away. It’s the eco system at work. We’re hoping that pink slime is following that pattern-and that last year was the worst outbreak that we’ll ever see. However, just in case, we’re still working on a solution.

What’s the Old Cure?

Up to now, the common knowledge was that bioslimes were associated with pool water that is low in calcium. The pink and clear ones seem to be equally likely to happen in water treated with chlorine, bromine or biguanide. The white and gray ones seemslightly more common in biguanide pools, but probably because a good number of those pools used simazine algaecides and didn’t use winter kits. All of the bioslimes seem to be more prevalent in pools that are not shocked often enough, or (for an as-yet unknown reason) shocks don’t last very long in the pool water. Often, the growths start in the pipes, hoses and filter—the opposite of algae, which always starts in the sunny areas of the liner.

To prevent them, we’ve been advising keeping the pool water balanced—especiallybefore it’s closed for the winter. Use a filter cleaner every year (maybe even twice a year). Shock regularly. Whenever you refill the pool, run 20-30 gallons of water from your garden hose out onto the ground before putting it into the pool. Bioslimes are often in your drinking water (in small quantities) but they grow very well in a hose sitting in the sun. Brush the pool often—especially under ladder treads, under the skimmer weir door, and under any folds or flaps in the liner.

We have several alternative treatments available at the store to kill an existing problem. some are cheap, some are expensive. The expensive treatments work better than the cheap ones.

What’s New for Chlorine or Bromine?

As an industry, we have to become more resistant to consumer (that’s you) demands for pools that require no maintenance. We have all been advising you to give your pool less care than we used to recommend. Until 1984, we had everyone shocking and algaeciding every week. However, once Baquacil hit the American market with monthly shocking, the chlorine manufacturers started recommending every other week for residential pools (commercial pools still add chemicals much more often than most homeowners).

Bioguard has come out with a new shock treatment for chlorine and bromine-based pools, called Bioguard Lite. it was designed to be less harsh to the pool than other shocks, and (used as directed) it will not raise your chlorine level as high. Using it at night, you should still be able to swim the next day. However, unless you want to do some complex testing and calculating (to see if you need to reach a higher breakpoint), we will want to test your water in July or early August just to see if you need to use a more harsh shock once in a while.

It probably isn’t a good idea to use the so-called “Safe” or “shock-and-swim” shocks that contain sodium or potassium monopersulfate on a regular basis—they don’t kill anything, and they give you false chlorine and bromine readings. We have a special test kit that can fix that, but it’s expensive.

No matter what shock you use, however, we definitely recommend shocking every week.

If you use Bioguard Back-Up algaecide or Target Non-foaming Algaecide we prefer that you use half as much, twice as often. If you use Bioguard Algae-All 60 or Target Non-Metallic Algaecide, use the lower dose weekly instead of the higher dose every ten days.

Ask us to test for your algaecide level (we can do it if you know which algaecide you use) sometime in mid-summer. Again, July or early August would be an excellent time.

What’s New for Baquacil or Softswim?

Bioguard is recommending that Softswim users buy Softswim C Test Strips, and test your “C” level every week. If it drops below 40 ppm, re-shock with your normal monthly amount. As with our chlorine customers, we also recommend that you use half as muchSoftswim A, twice as often, so that you are adding it every week, but you’re still using the same amount per month.

Based on Baquacil’s research, though, we would prefer to see you add half the normal amount of Softswim C, but whenever your shock level dropped below 80 ppm. For more exciting information, however, read our Baquacil recommendations.

For Baquacil users, we have several possible solutions, including the possibility of participating in a test being run by Baquacil’s research laboratory.

There’s nothing wrong with the dosage of timing of Baquacheck 50 or Baquacide 795, so keep on doing what you’ve been doing.

However, Baquacil has developed a new consumer test kit for Baquashock, so that you can now test for the right amount. The kit is much more accurate, though a bit more difficult to use, than the test strips that are now on the market. It’s much like the total alkalinity test that many chlorine users do: you add a drop of one reagent to turn your sample one color, then count how many drops of another reagent that it takes to turn it a different color. Technically, these kits will not be available to the general public until 1997 or 1998. However, we’ve been allowed to purchase a pretty good batch for our research project. If you wish to participate in one of our experiments, the kit will probably cost around $4.00—that should be what we are paying for them.

Under the new system, we will ask you to test your shock level every week when you do your other tests. If your level drops below a certain amount, you will add some. For most people the amount you use per season will not increase very much, if at all. However, watching how the level behaves should prevent problems, and identify potential problems before they get out of hand.

We will be offering two protocols this year. One is very aggressive, and was very successful in Florida research pools last year. It is part of the Baquacil research study, and all of its recommendations are approved by them. However, it requires a pretty high shock level, and lots of Baqua Boost. We will highly recommend it to anyone who’s ever had a bioslime problem.

The second protocol will be an experiment of mine. It should be less expensive, and logically should not work as well. However, for the average person who’s never had a bioslime problem (and probably never will) I’m betting that it will offer excellent protection for maybe $20 a summer and two minutes a week.

For details, please ask us about it in May—we still have to finish some work with the Baquacil research scientists. We may also be able to offer some sort of similar program to Softswim owners, but that’s still in the works.

What’s New for Everyone

It has become obvious that pink slime and uncontrollable cloudy water (a common side-effect) are much more of a problem in warm water: July 10 to August 20. We’re looking at unusual shocking techniques, Baqua Boost, Proteam Supreme, or other additives, along with a water balance in early to mid-July. Water molds do grow all year, and can become uncontrollable over the winter because you don’t see it happening until you take the cover off in spring. That makes your closing water balance and the quality of your winter kit more important than ever.

If this all sounds confusing, why don’t you join our Take It Easy™ Program? The registration fee is less than the cost of the winter chemicals that we give you (so it’s actually cheaper than free), we give you a personalized calendar with what to do and when for the whole summer, and we pay you if you follow our directions and you still get algae, cloudy water or a bioslime.

If you have any questions, please call or come in.

Next Page:

Previous Page:

Return To Top