ARTICLE UNDER CONTSTRUCTION:
PLEASE RETURN LAAAAAAATER…
Modern swimming pool design and maintenance have been well characterized and well known for the last 40 years. Still, there are lots of misunderstandings and misconceptions floating around the web, so, here’s Yucalandia’s take on how to have a clean sparkling pool while minimizing costs.
Healthy appealing-looking water is a pool owner’s first priority.
None of us like swimming in cloudy bacteria-laden water, so lets focus on the options and what works to keep our pools in tip-top shape. Just how do we get and keep pool water clear and clean?
There are 4 basic options here, depending on how much effort and how much money you want to spend, and also if you have access to natural areas and natural water. Old School is simplest option: you regularly drain the pool and refill it, like a bath-tub. Using a nice spring or clean creek makes this a snap. Simply divert enough clean flowing water to replace the pool’s volume once a day. If you have a 20,000 gal pool, you’d need a flow of about 800 gal. per hour or 14 gal. per min to completely turn over the water in the pool about once every 2 days. Why 2 days? At these relatively low flows, and no circulating pump(s), there are lots of quiet spots where very little mixing takes place. Even though
Don’t have a spring, creek or river on your property?
Here are some basics to keep your pools clear and sparkling clean by adding electricity and chemicals:
This route basically takes the pool owner to decide exactly
~ which type of disinfectant they want to use and
~ whether they prefer larger up-front costs
~ do they prefer regularly adding disinfecting chemicals & doing regular testing or
~ do they prefer buying equipment that makes the disinfectant chemicals automatically
Most North American pool owners focus their efforts on using chlorine to disinfect their pools, but there are alternatives like ozone or UV sterilization.
1. Properly sized UV filters do kill bacteria and algae & mold spores while the water is inside the filter , but the mercury lamps intensities drop after a year – unless you have a special scientific grade lamp with halide scrubbers in the lamp gas to scrub the tungsten deposits off the quartz envelope and redeposit the tungsten back on the filament. Since UV filters coincidentally only make minimal amounts of ozone and hydroxide radicals, water treated by UV has almost no residual disinfecting power, which means that they have almost no power to kill bacteria or algae out in the pool or on the pool surfaces. This means you have to add chlorine or bromine anyway to keep the pool clean.
2. The most important issues to keeping the pool clean are
a. to remove leaves and organic debris daily by skimming and filtering – which includes having a well designed plumbing system to pull organic debris from the pool,
b. to maintain stable free chlorine levels that keeps bacteria and algae from blooming, especially after Yucatan rains that inject high dosages of algae spores,
c. maintain stable free chlorine levels by lowering the high pH of Yucatan ground water by adding acid to reduce pH to 7.2 – 7.4 ,
d. maintain stable free chlorine levels by maintaining no algae blooms by adding organic algaecides or inorganic algaecides, like copper sulfate ,
e. maintain stable free chlorine levels by adding cyanuric acid to protect the free chlorine from Yucatans strong UV sunlight doses
That last thing is one of the big tricks to why ChuckD’s pool only needs 30 minutes of pumping – because his use of chlorine pastillas, tablets or pucks, because these tablets keep free chlorine levels stable and also have cyanuric acid – which the buckets of chlorine powders do NOT include.
If you check out the realities of the salt chlorination systems, you find that the Yucatecan ground water causes them to burn through at least $5000 pesos of filaments about once a year, along with using electricity 24 hours 7 days a week.
JiminChelem is on the right track. There is a point where bigger pipes very quickly do not increase flow. For people interested in learning about this, learn about head pressure, google it, or google charts of pump flows versus inches or feet of head. Head equals back pressure caused by pumping water uphill, or through elbows or other turbulence creators- When the diameter of the pipes is large enough, then installing bigger pipes does not reduce head pressure. Elbows increase head, so having fewer elbows and having no elbows close to the pump are bigger issues than increasing tubing size on pools. If you have an elbow right before the inlet or the outlet of the pump, the turbulence from the elbow reduces pumping efficiency a lot more than increasing pool plumbing from sizes larger than 1½” or 2″. Regularly skimming your pool and backflushing your sand filter keep the sand filter from plugging, which also increases flow and filtering & pool cleaning efficiency much more than larger pipes. Jim did not know exactly why, but he knows reality from practical experience.
ChuchD’s system really does only need 30 minutes of pumping because he obviously has a well designed and well maintained system that keeps enough free chlorine to stop algae blooms and bacterial blooms. ChuckD likely has a well designed pool plumbing system that sucks up the gunk and his regular and effective pool cleaning efforts are enough to keep his organic debris loads of leaves and dust low, and by adding cyanuric acid to stabilize and protect the pool’s free chlorine, he does not have to keep adding much chlorine and does not have to run his pump much. The big chlorine tablets keep his free chlorine levels stable by slowing releasing free chlorine as it is needed and by adding cyanuric acid at the same time. The only drawbacks to using pucks is that they are more expensive, and the pool can overdose with cyanuric acid over time if you do not ever change the pool water.
Since what ChuckD does seems to be successful, it might be a good idea to study him, his system, and the practical aspects of a system that works really well, with minimal effort.
Other issues not mentioned include:
– important issues like maintaining stable constant levels of “free chlorine”,
– the critical need for using “cyanuric acid” to protect free chlorine from destruction by UV from the sun,
– key factors in designing efficient pool plumbing systems, like surface extractors,
– “head pressure” or turbulence in designing pool systems,
– the specific performance curves for different pumps and matching the plumbing to the pump,
– how filter type and regular filter maintainence are much more important that tubing size
– residual disinfecting power.
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Feel free to copy while giving proper attribution: YucaLandia/Surviving Yucatan.
© Steven M. Fry
Read on, MacDuff.