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MPurcell's Achievements

Spa Savant

Spa Savant (3/5)



  1. try https://www.troublefreepool.com/forum.php
  2. No. Use the pH section to calculate how much dry acid you need to reduce the pH to 7.0 from where it is now. Then use the "Effects of Adding Chemicals" section at the bottom of the calculator to calculate how much that amount of dry acid will reduce TA. However, do not lower pH below 7.0 because it is not good for equipment or for people. The process is to lower the pH to 7.0 and then aerate to bring the pH back up to a high level, and then repeat the process until you get your TA down to where you want it. I'm not clear about your numbers, but if your TA is 300 and you want it to be 60, and your pH is high, say 8.0, then in 350 gallons: reduce pH from 8.0 to 7.0 requires 5.4 ounces by weight or 3.6 ounces by volume of dry acid The calculator at the bottom will probably give you a different number for the amount of pH reduction since the caluclation depends on many factors and is not very accurate at those numbers. The only way to do it really is to add chemicals and then use your test kit to get actual readings, and that will guide you. You must have a proper test kit such as the Taylor K-2006 for chlorine or K-2106 for bromine in order to get accurate readings. If the numbers mentioned are accurate, you will probably have to go through the pH reduction by acid and increase by aeration process a number of times to get TA where you want it. In my chlorine tub with calcium hardness of 125 ppm I run TA at about 80 ppm and my pH is stable around 7.4 or 7.5 when I don't do a lot of aeration.
  3. pH+ will also increase TA, so defeats the purpose. The only way to increase pH while not increasing TA is by aeration.
  4. I don't see why not. Depending on what is in the wipes besides bleach, however, you may be introducing a small amount of soap or other chemicals into the tub water as it contacts those areas when you get into the tub. The chlorine should oxidize the other substances, but it may increase your chlorine demand a little. Please learn about the use of dichlor if you haven't already studied it. You can follow the dichlor then bleach method sticky post at the top of this forum.
  5. If your CYA level is really 200 then yes, you should change out the water. However, if you have only had the tub for two weeks, it is hard to believe you could have a CYA that high. To get the CYA to 200 you would have had to put approx 220 ppm of chlorine in the tub with dichlor. To keep the tub at a normal level, say 4 or 5 ppm of chlorine every day, it would take quite a bit longer than two weeks to add enough dichlor to build up the CYA to that level. My advice: Do not listen to the advice given by any pool store. If you do, you will probably remain confused. You would probably get conflicting advice if you talk to different stores, or different people at the same store. Their culture is to sell expensive products. Read and study the information on this forum and on the trouble free pool forum (which is much more active than this one). Study until you understand what to do. You should probably follow the dichlor then bleach method which is a sticky post at the top of this forum. Or the how to use chlorine sticky at the other forum. Your primary sanitizer in a chlorine tub should be common household bleach, or liquid chlorine, which is the same thing but a little stronger. Get a good test kit which includes FAS-DPD test for chlorine, such as the Taylor K-2006 or the TFTestKits TF-100. A good test kit is essential to keeping your water in balance. You really need to invest the time it takes to study and learn so that you understand water chemistry enough to take care of your tub properly.
  6. In a bromine spa you don't need to use cya. If you established a proper bromide bank by adding sodium bromide each time you filled the tub, then the chlorine you add is almost instantly converted to bromine. You could bring the TA and pH down with muriatic acid. A pH of over 8 is not good for either water quality or equipment longevity. Ideally, pH should be between 7.2 and 7.8, and certainly no higher than 8.0. You could find the TA level that will keep pH stable and in range. Typically, that would be somewhere between 50 ppm and 80 ppm in most tubs, as long as you are not using bromine tabs or MPS. Bromine and chlorine both work well. I think it is a personal decision. A lot of people prefer chlorine for less smell and better feel. I have no experience with SWCG's or keeping the chlorine level up for several weeks while the tub is not in use, however, so I really can't comment. One thing is for sure, whether you use chlorine or bromine, you don't want to let the sanitizer level fall to zero, or even below the minimum effective level at any time while the tub is idle.
  7. No. You need a clear space where the shape of the tub will not be restricted. If you try what you asked, you would probably get rather quick wall failure, I'm thinking. That is if the tub is even flexible enough to fit in that space. Once blown up, the tub isn't very flexible at all. Plus the weight of the water is not insignifican, approx 2,600 lbs when full. I have a Coleman Lay-z-spa made by Bestway located in my garage.
  8. I have only worked with small amounts of water, so I don't have any experience with a large spa like yours. However, the same principles should apply no mater the size. Bleach is very close to neutral pH which means you really won't notice much if any shift in pH when you add bleach. There usually is a trace of Sodium Hydroxide in bleach as a buffer, but it is not enough to make much difference. I don't know what would be causing your pH to push up. The dichlor, bleach method, which I am also using in my tub, doesn't necessarily do that. In my tub, for instance, pH hangs around 7.5 and if I don't use any aeration at all, it actually drifts down one or two tenths of a point in a week or so. On the forums, they often say every pool and tub behaves differently. If you haven't done so, you might try buffering the pH with borates. Boric acid is not very expensive and the best way to add borates. Other than that, I don't have any suggestions. When the bather waste goes up, the amount of oxidizer needed to neutralize it goes up. You should add oxidizer after the spa is used. It usually only takes a little time for the bather waste to be neutralized, so if you are using bleach as the oxidizer, and you add the right amount after bathers use the tub in the evening, the chlorine level should be back down to the normal level by the next morning. If the chlorine is high the next morning, you have added too much bleach, and if it is low, you haven't added enough. You can adjust your bleach addition by testing until you know what you need based on the time in the water. If you get this right, there won't be any additional smell. You can use MPS, but as you may have read, MPS will throw off the chlorine readings of your test kit, so it will make it harder to be sure what you are doing. Also, MPS adds sulfates to the water which can build up if you use it regularly, and that may not be good for the equipment long term. If it were me, I would not use MPS at all, and just use bleach for both chlorine and oxidation.
  9. The dispenser usually has some sort of adjustment for the amount of bromine released. The ideal is to set it so that the bromine reading remains the same from day to day when the tub is not in use. If yours won't adjust down that far, then you may have to take it out for a bit from time to time. "Shock every week" is pool store speak for "buy my expensive products." Actually, if your tub is properly maintained, you should not have to shock at all, or at least not often. When I was using bromine, I think I shocked it twice in a 6 month period between drain and refill. Your floater should replace the daily bromine demand of the tub, and then when you use the tub, you should add enough oxidizer to exactly compensate for bather waste. If you follow those requirements, and never let the bromine level go below 2ppm, then you should never have cloudy water or any other problems. For reference, you could read the sticky thread at the top of this forum about bromine use. Incidentally, the best oxidizer for a bromine tub is regular household bleach, not to mention also being the most economical.
  10. I suggest you re-ask your question in the Portable Hot Tubs and Spas subforum. The repair guys probably don't even look here in the water chemistry section.
  11. You can put chlorine in if you want, but for four days at 65 deg you should be fine without. You can use the Ahh-some with chlorine in the water or no chlorine, it doesn't matter. You can also use Ahh-some in ambient temperature water, although it is slightly more effective at hot tub temps. Not familiar with the Javex brand of bleach, but just make sure that is has no additives such as splashless or scented. Usually, one treatment of Ahh-some is sufficient unless there is a major buildup of biofilm in the plumbing. You can tell by how much gunk comes out. You will see the residue discoloring the foam, and in severe cases, sticking to the sides of the tub. If the gunk is heavy, then do a second purge. If it's light, then one purge will probably be sufficient.
  12. It should not be necessary to drain. You have not put anything in the pool that would add bacteria, and the water has been at ambient temperature which is less than ideal for anything to grow in it. Once you get the power on you will balance the water and add sanitizer and all will be good.
  13. You can use hydrogen peroxide to neutralize chlorine. In this way, you could shock the tub to a fairly high level, and not have to wait for the chlorine to all come down naturally, but do it all in one or two days. I've done this fairly recently when super-shocking to try to get rid of combined chlorine, and it works well. When hydrogen peroxide combines with chlorine, it produces hydrochloric acid (or muriatic acid, the same chemical that is used as pH down) and water, so it will lower pH a little but is otherwise harmless. To do this, the volume of 3% hydrogen peroxide needed to neutralize X amount of FC is equivalent to the volume of 6% bleach that would raise the FC by X.
  14. If you have an allergy to chlorine, you may also have an allergy to bromine, since they are both halogens. But it may be worth a try to find out. With a bromine tub, you put a large reserve (usually about 50 ppm) of sodium bromide into the water upon first fill, and you use a daily dose of chlorine to activate the bromine. Chlorine converts the sodium bromide into hypobromous acid, and when the hydrobromous acid oxidizes the bather wastes and other contaminates, it turns back into sodium bromide. The conversion of the sodium bromide happens very quickly, so you really have no chlorine in the tub when you are soaking. If you keep the water balanced, and the sanitizer level up to the recommended levels, you can maintain a clear clean tub for many months. Here's a detailed post on how to use bromine: https://www.troublefreepool.com/threads/84-How-do-I-use-Bromine-in-my-spa-(or-pool)
  15. http://poolcalculator.com/ and also at https://www.troublefreepool.com/calc.html They are almost identical, but may be maintained by different people
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