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Posts posted by waterbear

  1. 22 minutes ago, dswanson said:

    As for why it's happening in the first place - it's due to not having the right chlorine level for the cyanuric acid in your pool water. Once that is set you can remove phosphates to make it harder for algae to reproduce.

    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.

  2. 17 hours ago, Euphanasia said:

    RDspaguy, thanks for the condescending opening line.

    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 

    17 hours ago, Euphanasia said:

    Everything is where it should be with the exception of the cyanuric acid, which I will be adding when it arrives. 

    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.

    17 hours ago, Euphanasia said:

    There is no "gunk" coming up from the jets. When they are turned on, there is a cloudiness to the water and the smell--which I now understand to be chloramines. But the point is that the water in the tubing for the jets is producing a smell when the jets are turned on, and I would rather have that happen before I get in the tub than while I'm in it. 

    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.


  3. 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).

    1 hour ago, RDspaguy said:

    I'm sure @waterbearcan explain it better

    No, @RDspaguy, you did as good a job as I could.

  4. 12 hours ago, antoanthemselves said:

    Oh man, you need a plumber to fix your hot tub. i think that's the only solution. Preparing by your own I think is too hard. But I hope you succeded.

    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.

    • Like 2
  5. 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.

  6. 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.

  7. This kit will fit the bill for you:


    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:


    Here is a stand alone Calcium Hardness test kit if you decide to go with the pool lab meter:


    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.

  8. 1 hour ago, mikensam said:

    Total Bromine was around 9, Free Chlorine about 3

    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


    1 hour ago, mikensam said:

    The readings looked good immediately afterwards, the Total Bromine was around 9, Free Chlorine about 3, and pH/TA were a little high so I added another 25g of pH down.

    had started to dry, in which case the readings are inaccurate.

    1 hour ago, mikensam said:

     Is the calcium hardness a really important part of testing

    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.

    1 hour ago, mikensam said:

    The readings looked good immediately afterwards, the Total Bromine was around 9, Free Chlorine about 3, and pH/TA were a little high so I added another 25g of pH down.

    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.

  9. 2 hours ago, mikensam said:

    if you dont mind, could you also give me your thoughts on this please?


    Its kind of the closest thing i can find to the taylor testing equipment that offers an option for all of the tests recommended.

    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.

  10. 2 hours ago, mikensam said:

    or the 3 step process please,

    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.

  11. 4 hours ago, mikensam said:

    how much should I be using?

    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.

  12. 4 hours ago, mikensam said:

    here is the back of the label for the Acti-Spa stuff 

    This is also dichlor, sodium troclosene is anther name for it along with Sodium 3,5-dichloro-2,4,6-trioxo-1,3,5-triazinan-1-ide and Sodium dichloroisocyanurate. To paraphrase William Shakespeare

    “What's in a name? that which we call Dichlor
    By any other name would sanitize as well.”


  13. 8 minutes ago, mikensam said:

    Re the 2nd paragraph, so i can use the standard choline granules I already have (photo attached) to oxidize the sodium bromide?

    Post the ingredients. If they are dichlor and nothing else yes. If they are trichlor I would not since trichlor is slow dissolving and extremely acidic. If they are fast dissolving they are most likely dichlor. You can always search for the sds (safety data sheets on the internet. I did fine the Clearwater SDS and it is dichlor.

  14. If it says you need to use chlorine then you can't use it with bromine. Most chlorine only mineral cartridges use silver nitrate as the source of silver, spa cartridges normally do not contain copper because of increased chance of copper staining and green hair at the elevated temperatures seen in spas vs pool. Some do contain zinc, which is similar to copper in its algaestatic effect.

    Cartridges designed for use with bromine, such as the original SpaFrog, use Silver Chloride in a calcium carbonate matrix instead of Silver Nitrate since silver nitrate will react with the bromine sanitizer to cause silver bromide to precipitate out of solution and cloud the water at best and cause silver staining at worst. Silver stains are impossible to remove.

  15. On 6/17/2022 at 3:14 AM, mikensam said:

    All other places I have seen always say heat up the spa before balancing the water, is there a reason you say not to please as I have just brought it up to temperature before I was going to start following the instructions, does this change anything?

    Sometimes it can take up to a week to balance the water (for example, lowering very high total alkalinity) and the spa needs to be uncovered so why pay for heat and also increase your evaporation until you are where you need to be and can keep the spa covered. It's just common sense.

    On 6/17/2022 at 3:14 AM, mikensam said:

    Also for the shock it says you can use chlorine, do you mean a chlorine based shock or actual chlorine granules because I thought the latter was a complete no no?


    Why do you think that adding chlorine to a bromine system is a "complete no no"? While it is true that you do not want to add bromine to a chlorine system because it will convert it to a bromine system it is also true that chlorine or MPS is necessary in a bromine system.

    To shock, or more correctly oxidize, the bromide bank in the water you need to add an oxidizer. Chlorine fits the bill. In fact bromine tabs are mostly chlorine, one step bromine products are mostly dichlor with some sodium bromide, and commercial two step bromine is sodium bromide and either dichlor or MPS (non chlorine shock).

    There is no such thing as a 'chlorine based shock', it's just chlorine (usually calcium hypochlorite or dichlor) and often contains unwanted ingredients such as copper based algaecides and water clarifiers. Shock is not a product, it's something you do to a spa or pool. In other words, it's not a noun, it's a verb! 😉

    As far as chlorine sources that can be used I prefer sodium hypochlorite (liquid pool chlorine or plain, unscented, unthickened laundry bleach) but you can use dichlor since the stabilizer (Cyanuric Acid or CYA) is not an issue in a bromine system, unlike a chlorine system that quickly becomes overstabilized since dichlor adds 9 ppm CYA for every 10 ppm free chlorine added. I tend to stay away from calcium hypochlorite since it adds 7 ppm of calcium hardness for every 10 ppm of  free chlorine added. Lithium hypochlorite is a good choice if you can afford it.  It's the most expen$ive form of chlorine and has no negative effect like liquid chlorine in a fast dissolving powder form


    Here are some posts that you might find helpful:






  16. First, please post what chemicals you are using (sanitizer, balancers, etc.) and post a full set of test results and how you obtained them (strips, a colorimeter (with strips, discs, or liquid or tablet reagents), a kit with liquid reagents (you mentioned using an acid demand test with indicates you are possibly using one of the Taylor or LaMotte test kits).

    On 6/16/2022 at 12:29 PM, TubShark said:

    Upon adding Sodium Bisulfate in .75oz increments to lower PH and waiting 6-12 hours in between, the PH did not change at all until roughly 6oz total was added over several days.  TA did decrease incrementally with each addition and eventually got to 50-60 ppm and the PH finally lowered to 7.6.

    Why did it take so long? You need to aerate the water to gas off CO2 which, in turn, causes the pH to rise. Hot tubs are easy to aerate. Just uncover them, turn on all the jets, aerators, and bubbles if you have them and run the tub. The small volume of water in the tub will rise in pH quickly and you are starting with an initial TA of 100 ppm which is not very high to begin with. A few hours of aeration will cause a pH rise and then you drop it again and repeat.

    Read these post for a better understanding of pH and TA:




    Also constant use of dichlor will cause your CYA to rise too high quickly (dichlor adds 9 ppm of CYA for every 10 ppm of free chlorine added).

    Crashing pH is usually associated with the use of trichlor which, IMHO, should never be used in a tub given the small volume of water and the extremely acidic nature of trichlor.

    You never mentioned if your TA stayed relatively stable or also crashed. If you TA was in range then all you need to do to raise the pH is aerate the water (uncover the spa and run the jets and aerators to gas off CO2 and the pH will rise). You do not need to add more baking soda unless the TA is too low.

    On 6/16/2022 at 12:29 PM, TubShark said:

    To make things more complicated, after about a total of 10 weeks of constant maintenance, adjustment, and use, I shocked the spa (to 10+ppm chlorine) and the PH crashed and never recovered, even after chlorine levels dropped back to normal levels.  At this point, no matter how much Sodium Bicarbonate I added, I could not get the PH to increase.

    What did you shock with, trichlor or dichlor? Shock levels of sanitizer will cause pH to read high when it's actually low, sometimes dangerously low. Once the santizer level drops you will see lower pH readings. Once again, you hae not posted any TA readings during this event. Baking soda (sodium bicarbonate) is not the best chemical to use to raise pH. A much better choice is borax (sodium tetreaborate decahydrate or pentahydrate). The decahydrate can be found in the laundry aisle of any grocery as borax and the pentahydrate is available at many pool and spa supply stores at a much higher price. If you go that route you want the product that requires acid be added with it and not the pH neutral product. Dose borax at approx twice the amoun that you would dose sodium carbonate (washing soda or pH increaser). Sodium carbonate will cause a sharp rise in TA which borax does not do. Unless you are using trichlor (in a swimming pool) then you have no need for sodium carbonate.

  17. It's pretty hard to determine the source of a scum line without further information.

    First, what sanitizer system are you using (chlorine, bromine, biquinde/peroxide, "mineral stick" with chlorine or bromine, ionizer. If you are using chlorine what type (trichlor, dichlor, liquid chlorine or bleach, calcium or lithium hypochlorite, salt water chlorine generator). If bromine are you using a one step or two step product, floater by itself, or one or two step with a floater. Are you using MPS to shock?

    Do you have ozone?

    You said it's not a chemical imbalance but I would be interested in your test results for the past few months, particularly pH and TA and how you test them.

    @RDspaguyand @CanadianSpaTech I think you see where I am  going with this.

    I have a few possibilities as to the source of your scum line but until I get some more information it's impossible to say what it might be.

  18. If you are using chlorine then you need to test for free chlorine (good chlorine that sanitizes), combined chlorine (bad chlorine that causes eye irritation, possible respiratory problems, and does not sanitize effectively), pH, Total Alkalinity (which is the buffer system that helps stabilize pH. If too high or two low you will have pH stability problems and this is a reading that DOES change so it should be monitored weekly). Calcium hardness (too low and you will have a foaming problem, too high and scale will deposit on tub surfaces and in plumbing. This should be monitored monthly once balanced. IF your fill water is high in calcium then you will need to add a descaler to the water weekly). CYA (cyanuric acid, chlorine stabilizer) which should be around 30 ppm. IF it is high then your chlorine is not available to sanitize since it's chemically bound to the CYA. IF too low your chlorine is more aggressive to swimsuits and people and people. IF you are using a stabilized chlorine source (dichlor or trichor) then CYA will continue to rise since dichlor add 9 ppm CYA for every 10 ppm of free chlorine added and trichlor add 6 ppm CYA for every 10 ppm added. Trichlor is not recommended for tubs because of it's very low pH, which can cause Total Alkalinity and therefore pH to 'crash' to dangerously low levels, in part due to the small water volume in a tub. IF you are using either trichlor or dichlor then you should test this weekly. IF you are using liquid bleach or pool chlorine and have established a proper CYA level then test monthly.

    Having a test kit that will test all the necessary parameters for a chlorine tub will  make your tub maintenance MUCH easier. NO need to worry

    48 minutes ago, wookinpanub said:

    that I might need to get a degree in chemistry to sanitize and balance my hot tub

    but there is a small learning curve which most people master in a very short time. It's your tub and you can do anything you want, even not put sanitizer in the water or fill the tub with jello (NOT recommended!) but remember, the reason to sanitize and balance the water is to minimize any health risks. Waterborne illnesses are no joke. Here is a link to videos on how to use the K-2006 test kit from Taylor Technologies. It's really very easy.


    AquaClarity is a weekly maintenance spa purge product that has nothing to do with proper water balance. In fact, here is a direct quote from the Ahh-some website: " Once the hot tub has been purged, refilled and your water balance chemistry is stabilized, your tub is now ready to begin using the Aqua Clarity as a Weekly Maintenance program." (emphasis mine).


    Bottom line, balancing and maintaining your water will prevent problems before they happen (such as your previous white water mold problem. FWIW, this problem is usually seen in tubs that use an biguinde/peroxide sanitizer system like SoftSoak or BaquaSpa and are not normally seen with either bromine or chlorine when the tub is properly balanced and maintained (which cannot be done with a a two way test kit that only tests sanitizer and pH).


  19. 19 hours ago, Unclere said:

    Can these tablets be used with sodium hypochlorite?

    All form of chlorine can be used together when added to a pool properly. For example, it is very common for a pool to be chlorinated with trichlor and shocked with cal hypo or sodium hypoclorite. The trichlor is contained in a feeder or floater and the shock is either broadcast over the pool water or predissolved and broadcast. IF a floater is used for the trichlor then it is good practice to remove it from the pool or to take the feeder offline when adding the shock.

    In this case I would assume you are using the cal hypo tabs in the correct feeder system and are shocking with sodium hypochlorite added directly to the pool water. However, the concentrated chemicals should never be mixed or stored near each other since this could lead to combustion or explosion.


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