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waterbear last won the day on June 27

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  • Birthday 02/24/1954

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  1. How big is your tub and how are you testing? There is a known interference with phenol red used to test pH and high sanitizer levels. 3 to 4 Tbls. of 7.5% bleach will raise 100 gal. 9 to 12 ppm over the starting point (usually around 3 to 5 ppm) and pH test will show this interference when sanitizer is over 5 to 10 ppm, depending on who makes the reagent. The effect of the interference in that the pH will read high when it is not. Your pH is not rising, it's still 7.4 and my guess is that you free chlorine is high when you get the high pH reading
  2. Only in a pool with no Cyanuric Acid (stabilizer). Once stabilizer is present the Free Chlorine has to be run higher to achieve the same sanitizing and Algae killing effect.
  3. So much wrong here. Algae blooms are not always caused by running chlorine too low for the CYA level. Also, FWIW, this information on CYA was first published by Ben Powell on Pool Forum (and was known since the late 60s because of the research carried out by John A. Wojtowicz of Chemcon but suppressed by the largest manufacturer of stabilized chlorine) and carried over to TFP, as was the BBB method which was also developed by Ben Powell. I as one of the original Mods on TFP when it first started and actually wrote much of pool school. However, when the board was sold to it's current owner there were some issues so I left and they removed my name from what I wrote but many of my posts are still there. The info on Borate is based on work that I did along with Chemgeek originally on Pool Forum and later carried over to TFP. Now, as far as phosphates go, this is just a moneymaker for pool stores. Algae nutrients are phosphate and nitrate. Phosphate is testable and Lanthanum salts will cause it to precipitate out (and cloud the pool and and clog the filter, this is how phosphate removers work). Nitrates are also testable. However, the only way to remove them is by draining and refilling with nitrate free water. Nothing for a pool store to sell you so no money to be made. Phosphates commonly enter pools by fertilizer runoff. Nitrates commonly enter pools either by runoff of fertilizer or sweat, feces, and urine, which EVERY bather adds, no matter how clean they think they are. Animal droppings are also a source. Now, as far as algae blooms go both nitrates and phosphates are algae food. Nitrates are more often the limiting factor in algae growth than phosphates so in most cases only removing phosphates has not effect. IF phosphate is the limiting factor then they do work but they are messy to use. A much better solution, IMHO, is to add 50 ppm borate for it's algaestatic properties and maintain proper FC for the current CYA level and shock to the proper level (which is all the SLAM procedure is. The reason TFP created the word SLAM was to end confusion on the fact that shock is a verb, not a noun. It's something you do by raising the FC and keeping it there until algae is killed and not adding a product called shock. Products called shock are nothing more than chlorine or MPS. Chlorine will kill algae, MPS won't but can help with persistant chloramines in certain cases) Hope this clears things up.
  4. His opening line was not condescending and I agree with it. I will add to his answer. The test strips (except for the salt titrator strips) are useless for balancing water for several reasons, top two being they do not have the required resolution and second being that while precise (multiple tests on the same sample will produce the same results) they do not have the accuracy (how close the results are to the actual value, i.e. the degree of error in the reading) of other testing methods. My suggestion is to get rid of the 7 way test strips and get a Taylor K-2006 test kit which uses the FAS-DPD testing method for Free and Combined Chlorine, pH with acid and base demand tests (acid demand test is very useful when lowering Total Alkalinity) Total Alkalinity, Calcium Hardness, and Cyanuric acid. Along with your salt titrator strips and, if you decide to add Borate to your water (a good idea) then either Lamotte or Industrial Systems since they use color blocks that are readable instead of the strips from AquaChek, Hach, and Taylor where the color blocks are very close shades of tan and just about impossible to read. Your problem is most likely caused by a combination of things but boils down to not maintaining adequate sanitizer while the spa is not running (no CYA, biofilm in the plumbing, not monitoring combined chlorine and shocking with chlorine when the combined chlorine is over .5 ppm). Once you get a decent test kit post your readings and we can take it from there This tells us nothing about your water. We need actual test results. We can spot things in the test results that will tell us a lot. The fact that you are having problems indicates that you can't interpret the test results and apply the appropriate actions. The cloudiness is the 'gunk'. The smell, if it is a strong chlorine smell is chloramines, indicates that your chlorine is being consumed, most likely by biofilm in the plumbing. IF an off odor it's most likely bacterial, once again indicating that there is biofilm or the organic load is too high for the chlorine. Post a full set of test results as a starter.
  5. Are you testing your water? If so how? A Salt water chlorine generator does not mean you no longer have to test, balance and shock your water. You still need to drain and refill every 3 to 4 months and purge the spa with each drain and refill. If your testing indicated persistent combined chlorine over .5 ppm then you need to shock (superchlorinate). No, @RDspaguy, you did as good a job as I could.
  6. You are posting in a thread that is well over a year old. The previous post indicates that he did fix his tub. This thread is now closed.
  7. IF you are having chlorine gas injected for sanitation be sure that your CYA is high enough since the gas is injected every few weeks normally. Green water after rain is usually an algae outbreak and the cure is to add chlorine. In other words shock the pool. The most compatible with chlorine gas is either liquid pool chlorine (or chlorine laundry bleach) or calcium hypochlorite (assuming your calcium hardness is not too high since it will add 7 ppm calcium hardness for every 10 ppm Free Chlorine it adds.
  8. add some chlorine! If your pool was green it can take a lot of chlorine to kill it. If it's not holding then it's being consumed. I would not use a copper based algaecide unless you like green hair, btw. You need to be testing for Free Chlorine and Combined Chlorine (and not with strips) What is your CYA level? If it's too low your chlorine will be destroyed by sunlight. If it's too high you will need to run higher Free Chlorine levels to keep algae at bay. IF there is more than .5 ppm combined chlorine then you need to continue shocking. Remember not to raise your chlorine higher than 12 to 15 ppm because you have a vinyl liner pool. Best bet, why don't you post a full set of test results (not done with strips) for FC, CC, pH TA, CH and CYA and we can take it from there.
  9. This kit will fit the bill for you: https://www.lovibond.com/en/PW/Water-Testing/Products/Test-Kits/Pooltester/Pooltester-Multipooltester-5-in-1-in-plastic-case IF you want a specific test for bromine you can add this one (which I would highly recommend because it will give you a bigger bromine scale than the 5 in one which will only test to 6.75 ppm by multiplying the FC by 2.25: https://www.lovibond.com/en/PW/Water-Testing/Products/Test-Kits/Pooltester/Pooltester-Bromine-pH Here is a stand alone Calcium Hardness test kit if you decide to go with the pool lab meter: https://www.lovibond.com/en/PW/Water-Testing/Products/Test-Kits/MINIKIT/MINIKIT-AF-416 I found these with a search on google and I'm in the US. You will probably have many more results that I get. Also check Amazon.
  10. https://www.watertreatmentproducts.co.uk/product/hardness-total-calcium-test-kit/ https://www.ukpoolstore.co.uk/acatalog/Lovibond_Calcium_Hardness___Total_Alkalinity_Tablets.html https://www.ukpoolstore.co.uk/acatalog/Swimming_Pool_Water_Testing.html https://www.lovibond.com/en/PW/Water-Testing/Applications/Pool-Water-Treatment
  11. Not from where I'm sitting. First, disregard the Free Chlorine reading if you have a scale for Total Bromine. If you don't then multiply the Free Chlorine reading by 2.25 to get Total Bromine. My guess is that your readings are much higher since the colors on the strip are very pastel which indicates bleachout because of high sanitizer levels that are off scale. The other possibility is that your photo of the strip was taken after 15 seconds and the strip had started to dry, in which case the readings are inaccurate. Yes, Total hardness, which is what strips test, is a combination of calcium and magnesium hardness. Magnesium does not cause scale deposits, high calcium hardness does. If your water is very hard then you would want to add a weekly dose of metal sequestrant or hardness reducer to help prevent scaling. It won't remove the calcium but will chelate it so it doesn't deposit as scale. On the other hand, low calcium (soft water) can lead to increased foaming in the tub. Ideally, calcium hardness should be around 130 to 200 ppm. First, there is no way to accurately determine that your Total Bromine was around 9 based on the resolution of the color blocks on the bottle, best you can do is a halfway point so if you were darker than 5 and lighter than 10 the best guess would be around 7. The Free Chlorine at 3 is much easier to determine since there is a color block for 3. IF we take that Free Chlorine reading and multiply it by 2.25 we get a Total bromine reading of 6.75 so given the accuracy of test strips (which is not great) it's safe to say your bromine is around 7 ppm at that point. My guess is that the chlorine you \added had not fully dispersed though the water at that point and when you retested later it had and the readings was much higher . You pH test indicates this since there is a known interference between the phenol read indicator used to test pH and high sanitizer levels. Both chlorine and bromine react with phenol red and convert it to either chloropheol red or bromophenol red. Both of these indicators have the same color changes as phenol red but at a much lower pH range and top out at pH of 6.7 and 6.8 respectively so the color in your picture that indicates a pH of around 8.4 would mean that all we know about the pH is that it is AT OR ABOVE 6.8.NEVER test pH after shocking. A good pH test should be accurate up to about 10 ppm bromine but many of the ones on the market exhibit this behavior as low as 3 to 5 ppm bromine. An alternative, if you want to spend the money, is a glass electrode pH meter but you will also need the buffer solutions to calibrate it and the actual electrode needs to be replaced, usually yearly.
  12. I'm not a fan of meters but I know that good test kits are hard to get in the U.K. This looks like an excellent unit however and the price is not that bad. The tests you are interested in are Total bromine, pH, TA, and Calcium Hardness so you will have to buy some additional reagents to test Calcium hardness. As far as needing the glycine reagent for bromine, I've never heard of that since chlorine oxidizes the bromide bank into bromine sanitizer and the fact that bromine tablets are mostly chlorine! The ONLY way you would have a bromine spa without adding chlorine is if you are shocking with MPS, which also creates an interference and causes the sanitizer to read high or if you are using a salt water generator and using pure sodium bromide and not a mixture of sodium chloride (to produce chlorine) and sodium bromide (to create a bromide reserve to be oxidized by the chlorine produced). I would use the Free Chlorine test and multiply the results by 2.25 to get your bromine reading (multiplying by 2 is close enough and much easier, btw). Before you buy it make sure you have a source to get the reagents since the website you linked ablve does not seem to carry many of them.
  13. You would use the dichlor for weekly shocking or after a very heavy bather load (such as a party). You want to use enough to raise the bromine above 10-15 ppm. I would start with a teaspoon per 100 gallons (about 375 liters), wait a few minutes and test the bromine level. If too low add a bit more dichlor and retest. If too high use less next time you shock. It's a bit of trial and error but you will quickly learn how much you need for normal maintenance in YOUR tub.
  14. Depends on whether you are doing 2 step bromine (create bromide bank with sodium bromide and daily addition of oxidizer to maintain bromine level) or 3 step bromine (create bromide bank with sodium bromine, shock, then add floater with bromine tabs to maintain bromine level and shock weekly with chlorine to above 10 ppm bromine to destroy organics from bathers in the water). When you add chlorine to a bromine system with an established bromide bank the chlorne converts the sodium bromide to bromide sanitizers (hypobromous acid) very quickly. IF there is not an established bromide bank (often the case when you are only using bromine tabs in a floater where it can take weeks to establish the bromide reserve) you have chlorine in the water, which will also sanitize, so all is good.
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