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quantumchromodynamics

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  1. I think that in many cases ozone is counterproductive. It is only helpful in a limited number of cases. And, when it is done, it needs to be done properly. Pumping it directly into the return line is not the proper way to do it. The correct way to use ozone is fairly complicated and involves contact tanks, off-gassing, etc. Here is a paper about ozone.
  2. Here is the post about lowering TA. However, before you do, you need to subtract the phosphate component. Spa Guard Spa Sentry is listed as Phosphate Buffer 36.3 %, with a specific gravity of 1.36 grams per milliliter. 1 quart = 946.4 milliliters = 1,287.1 grams total product = 467.2 grams of phosphate. pKa for phosphoric acid: pKa1 =2.15, pKa2 = 7.21 and pKa3 =12.34 Since the product is listed as pH neutral at a pH of 7.5, then 66 % should be in the form of Dipotassium phosphate (K2HPO4) and 34 % should be in the form of Monosodium phosphate (NaH2PO4) on a molar basis. [edit]The mix might contain monopotassium phosphate instead of monosodium phosphate. Either way, the correction is about the same. For example, at a pH of 7.8, the correction factor would be 57 ppm instead of 59 ppm.[end edit] There should be 2 moles of Dipotassium phosphate (K2HPO4)) (174 grams per mole x 2 = 348 grams) and 1 mole of Monosodium phosphate (NaH2PO4) (120 grams per mole). 348 grams + 120 grams = 468 grams. Since there are 3 moles of phosphate ions, at a pH of 7.8 about 80 % will be in the form of HPO42-. That makes 2.4 moles of HPO42-. TA is reported in units of calcium carbonate equivalent. 2.4 moles of HPO42- equal 1.2 moles of calcium carbonate. Calcium carbonate is 100.1 grams per mole x 1.2 moles = 120 grams CaCO3. 120 grams CaCO3 in 400 gallons of water = 79 ppm. Volume.............subtract from TA 300 gallons............105 ppm 350 gallons............. 90 ppm 400 gallons..............79 ppm 450 gallons..............70 ppm 500 gallons..............63 ppm MSDS In your case, if your tub is 539 gallons, then you should use a TA of 200 - 59 = 141 ppm in the pool calculator. Since you have added 2 ounces of dichlor, then your cyanuric acid should be about 14 ppm. Cyanuric acid does not always register very well below 20 ppm. You should assume that you have 14 ppm of Cyanuric acid and enter that into the box for cyanuric acid. Typically, when lowering TA, you want to lower the pH to about 7.0 using muriatic acid, and then aerate to raise the pH. Keep doing that until the TA is correct.
  3. The Total Alkalinity is composed of multiple components, including carbonate, cyanurate, borate and phosphate. The CSI calculation uses only the carbonate portion of the TA. The pool calculator has a correction for cyanurate and borate when entered in the boxes. It does not correct for phosphate. To get the correct CSI, you need to subtract the phosphate component of the TA.
  4. The key is consistency. You should maintain the bromine in the 2 ppm to 5 ppm range. Ozone can help by oxidizing bromide to bromine. As long as the bromine does not drop below 2 ppm, then 2 ppm is fine. If you find that the bromine ever goes below 2 ppm, then you need to maintain the level slightly higher. Read Waterbear's post on bromine. http://www.poolspaforum.com/forum/index.php?showtopic=26324
  5. Assuming that your tub is 400 gallons, 1 tab per day will add 12 ppm of chlorine and 7 ppm of cyanuric acid per day. Your chlorine is probably very high, and the cyanuric acid is probably over 200 ppm. The itching can be from the pH being too low, the chlorine being too high or from bacteria caused by low chlorine or by the cyanuric acid being too high for the chlorine level. The chlorine is probably not registering on the strips because it is too high and bleaching out the color. You need to dump the water and the test strips. Refill, follow Nitro's dichlor/bleach method and use the Taylor K-2006 test kit. http://www.poolspaforum.com/forum/index.php?showtopic=13634 http://www.poolspaforum.com/forum/index.php?showtopic=18706 http://www.poolspaforum.com/forum/index.php?showtopic=23090
  6. I recommend against test strips. If you want a faster chlorine test, then get reagents R-0001 and R-0002 to test for FC. You will also need part 9056. Part 9056 This is only good for a quick test and bleaches out at high levels. It should not be used as your primary test.
  7. The rate at which chlorine is depleted by ozone is dependent on the pH and the concentrations of chlorine and ozone. Ozone reacts with the hypochlorite ion, but not hypochlorous acid. The pH determines how much of the chlorine is in the form of hypochlorite and how much is in the form of hypochlorous acid. pH........HOCl.......OCl-.......HOBr.........OBr- 7.2........66 %........34 %.......96 %..........4 % 7.5........48 %........52 %.......94 %..........6 % 7.8........33 %........67 %.......87 %........13% 8.0....... 22 %........78 %.......83 %.........17 % There are two different reactions of ozone with hypochlorite ions. O3 + OCl- --> 2O2 + Cl- 2 O3 + OCl- --> 2O2 + ClO3- The first reaction accounts for 77 % of the reactions and the second reaction accounts for 23 % of the reactions. The overall net is: 1.23O3 + OCl- --> .77Cl- + .23ClO3- + 2O2 As you can see from the chart above, the rate of chlorine loss will be 2.3 times higher at a pH of 8.0 than at a pH of 7.2. Most ozone used in a chlorine tub goes into destroying chlorine. CD (corona discharge) ozonators will destroy much more chlorine than UV ozone generators. If we assume that your all of the ozone (0.250 grams per hour) goes into reacting with the chlorine, then every hour your ozonator will remove 0.3 grams of chlorine (measured as Cl2). This would be a maximum amount of chlorine loss due to ozone. The actual loss would typically be less, and would depend on multiple factors, such as ozonator run time, pH, temperature, contact time, how well the ozone is mixed into the water etc. Adding 20 ppm of cyanuric acid should help reduce the rate chlorine loss because most of the chlorine will be bound to cyanuric acid. I don't think that ozone has much of a reaction with chlorine that is bound to cyanuric acid. Volume......................loss per hour.......... loss per day 300 gallons.................0.264 ppm.................6.3 ppm 350 gallons.................0.227 ppm.................5.4 ppm 400 gallons.................0.200 ppm.................4.8 ppm 450 gallons.................0.176 ppm.................4.2 ppm 500 gallons.................0.159 ppm.................3.8 ppm The same thing happens with bromine. However, as shown in the above chart, there is substantially less hypobromite ion concentration for any given pH. DMH (The carrier base in bromine tabs) might provide some protection for bromine in a similar way to how cyanuric acid provides protection for chlorine. However, that's less certain. Some bromine is attached to the dimethylhydantoin. However, I do not know the equilibrium constants for bromine with DMH. Multiple sources indicate that the level of dimethylhydantoin in the water must be limited and should not exceed 200 ppm. 1.23O3 + OBr- --> .77Br- + .23BrO3- + 2O2 Ozone + hypobromite ion --> bromide ion + bromate + oxygen gas Ozone will also combine directly with bromide to form bromate: Br- + O3 --> BrO3- The formation of bromate will result in the loss of bromide ions over time. The use of tabs should replenish the bromide ions faster than they are removed. In addition, the ozone will oxidize bromide ions into bromine again. Br- + O3 --> O2 + OBr- Which quickly combines with water to become hypobromous acid. OBr- + H2O --> HOBr + OH- Therefore, for bromine, you have loss of bromine as well as gain. As long as there is a sufficient bromide ion concentration, there should be more bromine created than lost. When the water contains 50 ppm of bromide ions, most of the ozone will be used oxidizing bromide to bromine. Reference
  8. One part says this: However, another part says this: So, some conflicting information. You can always contact the manufacturer at their website to inquire about questions. Also, when using a pdf document, the "find" box at the top of the document is very helpful.
  9. It looks like a typical salt system. They just use Magnesium chloride and Potassium Chloride to add the salt instead of sodium chloride. The only thing the system needs is the chloride. The sodium, magnesium or potassium are irrelevant.
  10. Why wouldn't a manufacturer publish a manual? Don't people need to know how to operate them?
  11. http://www.premiumleisure.com/Manuals/MarklllOM.pdf http://www.premiumleisure.com/Manuals/nov07/OverSeasMarklllManual.pdf
  12. All else being equal, I think that a thicker slab does translate to a stronger slab. I generally prefer to over-engineer things to prevent problems down the road. I usually prefer thicker concrete, a higher psi, larger diameter rebar, closer spacing etc. I also want to point out that the reinforcing rebar or wire mesh is important not only for strength, but for creating an equipotential bonding plane. An equipotential bonding plane is necessary to help prevent voltage differences between different parts of the pool area.
  13. The pool calculator is handy for calculating the correct doses of chemicals to add. The correct amount of borates is 50 ppm. Boric acid is only added at the beginning. It is not used for adjusting the pH. Boric acid is mostly pH neutral due to its high pKa of 9.14. See this post for how to do a three step bromine program. Make sure that you add sodium bromide salt at each fill up. The total alkalinity needs to be wherever it keeps the pH stable. If the pH is constantly too high, then the TA (Total Alkalinity) is too high. If the pH is constantly too low, then the TA is too low. When the TA is right, the pH will remain stable. Do not feel like you have to set the TA at any predetermined level or range. A TA of 100 ppm is usually too high for a hot tub. A high TA causes the pH to rise due to the off gassing of carbon dioxide, which is in equilibrium with the bicarbonate ions. It is important to measure "Calcium Hardness", not "Total Hardness". A Calcium Hardness of 160 ppm is a bit high for a hot tub. I recommend a lower level of closer to 100 ppm. Use the pool calculator to calculate your CSI. If your tub is plaster or has grout, then you want a CSI of 0.0 to about +0.2. If your tub is plastic or fiberglass, you want a CSI of -0.3 to 0.0. A high CSI will cause scale and precipitation of calcium carbonate. I would use the softened water and then add back in the correct amount of calcium. To raise the pH, try aerating first. Aerating causes the carbon dioxide to off gas, which raises the pH. HCO3- + H+ < > CO2 + H2O If aerating does not work, you can use Borax to raise the pH. I recommend against using sodium carbonate as it is most likely to cause a precipitation reaction. If your pH is very low or chronically low, add baking soda to increase the TA. I highly recommend that you get the Taylor K-2106 FAS-DPD test kit.
  14. chem geek's recommended rule-of thumb is to add 5 fluid ounces of 6% unscented bleach or 7 teaspoons of 43% MPS per person hour of soaking. This seems to work well for most people as long as they adjust the amounts based on their readings. I think that you could add MPS or bleach after soaking. I recommend bleach because the MPS adds sulfates that some people might have an adverse reaction to. If you use a bromine floater, then you would use substantially less bleach or MPS after each soak. If you shock after each soak, then you should not need the weekly shock. The key is to maintain an adequate sanitizer level at all times. Your floater (if you are using one) will provide a continuous bromine supply. You should try to use the minimum amount of tabs as possible to reduce the buildup of 5-5 dimethylhydantoin. 5-5 dimethylhydantoin is the carrier chemical for the bromine in the tabs similar to how cyanuric acid is the carrier for chlorine in trichlor or dichlor. You should add enough bleach or MPS after you soak so that there is a sufficient level for your next soak (about 4 ppm). Some people have their floater set to supply most of their bromine demand and use very little supplemental oxidizer. 1.3 ounces weight is equivalent to about 1 ounce in volume of MPS. 4.6 teaspoons of MPS are about 1 ounce (weight) There is a two step bromine program and a three step bromine program. The three step program uses a floater and the two step does not use a floater. See this post where waterbear describes the three step bromine program. If your ozonator is working properly, it will oxidize some of the bromide to bromine and you will be able to use less bleach, MPS or bromine tabs.
  15. There are two types of ozonator, UV and Corona Discharge. You probably have the UV, which uses a UV bulb. If the light is out, then you need to change the bulb. The bubbles will be produced either way because the air is drawn in by a venturi. When the air bubbles contain ozone, you should smell a faint fresh smell, like after a thunderstorm.
  16. Make sure that the concrete deck contains reinforcing wire mesh or rebar. Very important to create a equipotential plane.
  17. Does the person you bought the tub from have any paperwork or other information? Did they get it from Costco? Are there any labels anywhere? I think that Infinity went bankrupt and now operates under Infinity and Raindance You could contact Raindance/Infinity for assistance. http://www.balboawatergroup.com/Manuals---Instruction-Sheets# http://www.infinityspas.net/about-us.htm http://raindancespa-mfg.com/
  18. I really don't think that properly maintained chlorine levels would cause many problems with lacquer. There really shouldn't be that much chlorine getting into the air. Adding 20 ppm of cyanuric acid would help, but that means that you would need to maintain a higher FC level of about 1.5 ppm. I think that the humidity would be more likely to cause problems, especially if the lacquer is a water-based lacquer vs. an acrylic based lacquer. I think that a good polyurethane or clear epoxy would do better. What type of wood was used? You should check with an expert that specializes in these types of finishes to see what they recommend. For indoor rooms, air quality depends on good management. There should be enough fresh air supplied to the room to prevent the buildup of chemical fumes or excess humidity.
  19. The poster notes that the pH was measured as "normal". However, with a reported TA of 25, I suspect that the pH has probably been very low. Perhaps, not currently if it was recently raised, but I think that it is highly likely that the pH has been well below 7.0 for a while. ___________________________________________________ nelleldred, Too much chlorine, or disinfection by-products, can cause eczema, which can cause rashes and hair loss. Inadequate disinfection can allow bacterial infections, such as Pseudomonas aeruginosa, which can cause skin rashes and hair loss. If you are having a difficult time managing contaminants, bacteria, chloramines or disinfection by products, such as trihalomethane, you might want to consider getting some sort of supplemental disinfection system, such as ozone or UV. Note: Ozone can't be just pumped into the return stream; it has to be done properly. Here is an article about an indoor pool that needed to add ozone. Here is another reference about using ozone properly. Here is another reference that you might find helpful.
  20. I suggest that you get real TSP from the chemistry store. You could also get boric acid at the same time to add 50 ppm of borates. http://www.chemistrystore.com/ http://www.chemistrystore.com/search.cgi?keywords=trisodium+phosphate http://www.chemistrystore.com/search.cgi?keywords=boric+acid I also strongly recommend a good test kit, such as the Taylor K-2006 http://www.amatoind.com/taylor-k2006-test-p-555.html
  21. When you say that the pH was "normal", what does that mean? With an alkalinity of 25, I suspect that the pH is very low. In fact, an alkalinity of 25 ppm is a warning sign that whoever is managing the chemistry does not know what they are doing. If you have a low pH and no cyanuric acid, a chlorine level of 12 to 14 ppm will be very corrosive. If the pH is very low, you might see other problems, such as tooth damage. What are the following chemical levels: Free chlorine Combined chlorine pH Total Alkalinity Calcium Hardness Cyanuric acid Since this is a commercial pool, there should be records of all of these readings. Ask to see the records. We need to know the readings over time, not just what they are now. What type of chlorine is being used and how is it added? Is there a heater? What is the pool temperature? What size is the pool? Is it a concrete pool? What does the water look like? Is the water clear or cloudy What does the water smell like? Is this an indoor or outdoor pool? Can you give a list of all chemicals you have on site? Who is in charge of the chemistry? How often are readings taken? Have there been any other types of health complaints, such as respiratory ailments?
  22. I pulled a motor start capacitor from the back of an old 1.5 hp Dura-glas pump. The dimensions are about 23/4 inches long by about 17/16 inches in diameter. Here is the information from the capacitor: Aero M 161-192 MFD (microfarads) 110VAC...... 60 Hz 610807-2 677-9247-01 Example Note: The dimensions in this example are mislabeled. The inches are noted under the mm column. I think that this capacitor should work for you. Any local place should have this in stock or an equivalent.
  23. That is my main point. The feeder should supply only the amount that is needed when the tub is not being used. That way, the tub owner does not need to add every day, only when they use the tub, and only the amount needed based on usage, which may be sporadic. The primary problem I was trying to avoid was ending up with too much bromine. Basically what I am saying. Test and adjust when you use. Since you don't know how much the tub will be used, it's hard to adjust the feeder to supply the correct amount. However, once the tub is used, you can add the correct amount based on usage.
  24. I think that you could probably use the 161 - 193 MFD or the 189 - 227 MFD, just make sure that the dimensions are the same. BC161 or BC 189 MOTOR START CAPACITOR, 161-193 MFD 115V BC-161 MOTOR START CAPACITOR, 189-227 MFD 115V BC-189
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