dlleno

yes I have no issue acknowledging the uncertainty, and in fact the evidence you point out, suggesting the likelihood of oils and grease, as part of if not dominating the volume of material released in my experiments. But we should also point out that the uncertainty goes both ways, and while the abstract of the paper you cited is quite clear that chlorine did provide measurable attenuation, one cannot conclude that proper sanitation will in fact prevent all biofilm growth: "Results showed that the biofilm was able to accumulate on coupons and in the filter systems of reactors treated with either 13 mg/L free chlorine or 10 mg/L polyhexamethylene biguanide (PHMB).

I'm afraid you may need to check with a local dealer for diagnosis, or even the manufacturer. Its very difficult to diagnose here, but just for kicks and giggles lets assume that "FLO" error code means that there is insufficient water flow through the heater. I will also assume here (which is risky, so keep that in mind!) that you have two jet pumps and a circulation pump. Does that sound correct? I'm making lots of risky assumptions here... So all those assumptions lead me to suggest that the "motor" or pump you are interested in, is the one that supplies water through to heater. I may be way off here, to assume that you have a separate circulation pump with 2 jet pumps, but if this is correct, then the circ pump will be smaller than the other two pumps. Typically "separate circ pumps" do run all the time. Anyway, if I'm at all on the right track here, Its the circ pump that you want to check out. it could be worn or not working at all. and air lock suggest a faulty design ... or a fault in the plumbing. On the other hand, does your tub heat and maintain water temperature just fine when you are not using it? Can you can verify that your circulation pump is working (by putting your hand over the heater outlet). When you say the tub "cuts out" do you mean that your problem is that the jets quit working when you are in the tub? that would suggest that the jet pump(s) are starving the circ pump

just to add my own experience to this advice. I find, as many others have, that TA above 50-60 is a recipe for pH upward drift. After my initial fill, I run my jets to raise pH without raising TA, and then reduce both by adding dry acid. I do this until I achieve TA=40. Still, pH rises and to control this I use very carefully measured, small amounts of dry acid which results in TA as slow as 30ppm. As the spa gets used, the 'net acidic' behavior of the chemistry requires that I add Sodium Bicarb to keep build TA back up and control pH. TA=30 is very low, and you risk a precipitous drop in pH, so you have to watch this very carefully. By the time my water has passed the half way mark of its natural life, I find that TA=80 is required. Experimentation with your own spa is required to dial it in.

those are good numbers, but I have to ask: are you using a true Free Chlorine test to measure bromine? or you are really measuring bromine when you say "FC". Also, the fact that you have 30ppm CYA suggests that your tabs have dichlor in them. CYA is a don't care in a true bromine spa; thus, over time, the accumulation of CYA in your spa isn't doing anything useful. most of the folks here, including me, heavily favor the Taylor test kits, because they are so accurate and easy to read. I'm not familiar with the kit and strips you are using, although I tend to distrust "strips" in general. what you could do, to improve the accuracy of your tests, is to correlate them with a Taylor test found at a local pool store. Find a store that has such a capability, take your water into them and ask them to test it. then test it yourself and compare results.

yes, true enough. especially the first release -- all that white stuff: its impossible to know what that stuff really was; whether the other products contributed to, or influence its appearance or not, I will never know. What does white water mold look like? Anyway, the important part was ahh-some removed it. I agree that one can never be certain without direct test evidence that any given material is biofilm. But given that biofilms can be chlorine resistant, and given the plethora of information available, I think we can reasonably conclude that it is just as fallacious to assume that no biofilms were released in the experiment, or that biofilms cannot be present without an unusual chlorine demand. The reason I suspected that biofilms were released wasn't well described in my post, but there were three major ones: 1. The appearance of the material in the 2nd Ahh-some purge (the brown stuff) was remarkably similar to that removed by Ahh-some last winter (following the SeaKlear purge), when I was attempting to correct a known problem with the new spa. no doubt oils and other "non biofilms" were part of both experiments. 2. Having used three other products to purge the spa, the evidence favors material that the others didn't touch. I would expect the other products to have purged oils and greases and lotions and what not, but the data show that these products released none. 3. After having treated my filters with a traditional degreaser, the ahh-some still released material from the media, and one can reasonably conjecture that it was biofilm because all the oils and other material would have been removed by the degreaser, at least in large part. oh-- yes thanks to waterbear: the annoying center justification can be remedied by enclosing your text in the BB code "left" enclosed in brackets. be sure to pair this code with a corresponding "/left", also enclosed in brackets! Also note that when you edit, the system likes to strip BB codes and they end up disappearing. now if we could just eliminate the annoying "mysterious dark screen" and the add popup. I'm about ready to leave this forum on account of that. is TFP any better?

Bromine is an alternative to Chlorine and often used in hot tubs as the sanitizer. I'm not a floater guy but many use them effectively. You'll want to investigate the ingredients of the bromine tabs you are using. some, including yours, have chlorine in them -- but the answer to your question depends on whether or not your spa has built up sufficient bromide reserve. With sufficient Bromide reserve in the tub, adding dichlor simply oxidizes the bromide into bromine. I'd encourage you to read the bromine sticky here by waterbear; it lays out the principles very nicely, and seems to fit your preference as well (for the floater) I try to keep things simple -- I add sodium bromide salts once, at startup, and then add granular dichlor by hand (no floater). but as I say the floaters can work -- you just need to dial them in so that you are not over sanitizing your spa. (10ppm bromine is over sanitizing). You'll have to tell me what "our oxidizer thingy" is. is that an ozone generator? you don't need to "look into the dichlor if we can mix that with bromine". Your bromine tablets contain chlorine so you don't need to worry about that. look up waterbears' Bromine article and you will find what you need to know there.

just FYI, my TA drops to 30ppm when my water is new, and this is a consequence of controlling pH rise with dry acid. low TA is just a requirement to avoid pH rise -- you just need to watch out to insure that it does not go too low, or you risk a precipitous drop in pH.

+1 my experiments have shown that unusual sanitizer demand is a clear indication that biofilms are present. if you have greater than 25% decay over 24 hours, without ozone present, then you need to purge and shock (at the same time, with Ahh-Some) Note that I also have shown that gunk (and the evidence suggests even biofilms) WILL form, over time, even in a purged spa that has been properly maintained. So you gotta get right to the ahh-some purge as suggested. I use this product exclusively now -- having tested it against four other products that are not worth the packaging they come in, at least imho. The fact that you are using a foam down type product suggests oils and such from bathing suits, lotions, soaps, whatever. +1 for the scumball or other similar products designed to collect oils. Nevertheless, these things can and do accumulate despite best efforts. The more oils and such you can remove (or never introduce) the better. with the problems you have identified, I would suggest that you might require a 2nd ahh-some purge, which will at least give you the peace of mind that all is clean. you can see my recent post on the purge product shootout, but the bottom line in your situation I would 1. remove your filters. Soak them in in filter cleaner/degreaser + ahh-some 2. dose to some high level of chlorine, i.e. something like 10-20ppm. this is to kill the biofilms released by Ahh-some. 3. add 1 tsp ahh-some per 100 gallons of water 4. run the jets per label directions 5. drain and fill. re-dose with ahh-some. Note that If you can't drain chlorinated water, then treat with hydrogen peroxide to neutralize the chlorine. per chem geek, use the pool calculator to find the approximate amount of 6% bleach that will achieve the ppm level of chlorine you dosed to. -- then use about that amount of peroxide to neutralize your water before draining. 6. if the amount of material released by the 2nd ahh-some purge is very small, wipe it up with a cloth, rinsing in a separate solution of ahh-some. repeat until you have a clean spa, dosed with ahh-some. if the amount of material released by the 2nd ahh-some purge is high, then drain. repeat until you have a clean spa dosed with ahh-some 7. hose down your filters. then install them in your ahh-some dosed spa. do the wipe/rinse trick again until no more biofilm residue is left anywhere. 8. When you are satisfied that all is clean, remove your filters, hose them down, drain the spa, and start over with a fresh clean fill.

Can you tell us how you are establishing your bromine levels? and how are you measuring it? Also -- I assume here that TH means total hardness -- how are you measuring this? Many have reported success at 200 ppm Calcium Hardness, measured by the Taylor drop test, but many others of us favor lower Calcium levels than that (I am currently at 140). Also why are you targeting TA of 95-120?. For a portable acrylic hot tub, that is high, and I would expect you to have problem with pH drifting too high. Moreover, with TA that high, about the time your pH drifts to 7.9 your water may start precipitating calcium (Saturation index will exceed .6) . So I would highly recommend using a scale control product. Note that many of us here find success by targeting a lower TA -- I am running 40-50ppm right now. 10ppm bromine is high. I run my bromine spa at 4-6ppm. in a Bromine Spa, CYA is is not as important. How are you adding your sanitizer? granular dichlor contains CYA so most of us here do not "add" CYA to our spa water. we just allow the dichlor to contribute to CYA naturally, until 35ish ppm is achieved. use the pool calculator to find out how much that is -- for a 500 gallon spa its only a half cup or so. Once you achieve 35ppm CYA ,then it will keep rising if you keep using dichlor. thats why many of us here switch to bleach at that point. I'd encourage you to read the "dichlor then switch to bleach" posts here, on that topic. Also -- if I were you, before I used the spa even once I would purge with a product called "Ahh-Some". follow label directions. With a 2nd hand spa which has not been regularly maintained -- and even if it had been properly maintained -- I would highly recommend the Ahh-Some purge. be prepared for an astonishing amount of yucko to appear.

Silk Balance Clean Start. One normally does not think of this as a biofilm removal product, but the local dealer touted that it would be good for that. I removed my filters, placing them into a solution of traditional filter cleaner and added the prescribed amount (56 oz) of Clean Start to my 6-month old well-maintained water. This product is nothing more than Borax in an expensive container. It accomplished absolutely nothing except to produce a little foam and drive my pH through moon, but It released no contaminants. Not even a spec. I consider this one a placebo. I do like the container though it helps me scoop out water from the molded seats when I drain. Aquafinesse Spa Clean. Same result: absolutely nothing released. A complete waste of 1000 gallons of water. Another placebo. Natural Chemistry Spa Purge. This product released a very tiny amount of contaminants an amount hardly worth noting, in fact. What Spa Purge does is create foam -- truly epic amounts of foam. I had to shut the jets off to avoid treating my lawn with this stuff. But it really didnt do much of anything useful. I was left with the impression that specific foam producing agents have been added to this product, just for the effect. Ahh-Some. After three successive but unsuccessful attempts to clean my pipes with the above products, I refilled yet again and put in the prescribed amount of Ahh-Some. Woh. I got all kinds of white and off-white sticky gunk on the sides of my spa. The absence of brown gunk puzzled me, and I began to wonder if the previous three products might have contributed to or influenced the result I was now seeing. Unsure if the single Ahh-Some purge was completely successful I drained and filled again, and treated again with Ahh-Some. This time I got a boat load of brown stuff more along the lines of what I was expecting originally. Unsure if the 2nd Ahh-Some purge was successful I drained and filled again, and treated for a THIRD time with Ahh-Some. I got nothing. yippie! Conclusions: 1. Biofilms DO form even when you start out with a clean spa and when your water has been well maintained. Prior to this experiment I had purged with Ahh-Some, and 6 months later my water was still clear and there was no unusual sanitizer demand. 2. Ahh-Some is, by leaps and bounds, superior to the other products I have tested. For the purpose of removing biofilms, the other products I tested just do not perform and are useless for the intended purpose, in my opinion. 3. Chlorine shock cannot be depended on to remove biofilms. Note that prior to purging with Ahh-Some the first time, I shocked to 50 ppm Chlorine, and I still released copious amounts of biofilm. Im not saying the practice is fruitless or that it wont provide some attenuation. Im saying it wont remove biofilms outright especially those that are chlorine resistant. I acknowledge that not many have purged their spa with new/clean water. Thus, I suspect that the above products, particularly Natural Chemistry, would surely produce some effect (even an impressive one) under the conditions where most people would purge when there is a known problem. Encore: So you think your filters are clean? Think again. I had a squeaky clean spa, dosed with Ahh-Some, just sitting there and I couldnt resist the opportunity to see how clean my filters were. So I installed them into their normal positions and held my breath: instantly I saw new brown deposits accumulating on my walls again! This time the amount of material was small, and I was able to wipe it up with a soft cloth which I rinsed in a separate solution of ahh-some. That process took about 30 min. Conclusions; 1. Biofilms can form in your filters even when both they and your water are impeccably maintained. Ordinary Filter cleaner/degreaser is not sufficient to clean the biofilms from your filters 2. One again, Ahh-Some rules. From now on I will be cleaning my filters with a solution of Ahh-some plus some degreaser to be decided later. I might even use Ahh-Somes own filter cleaner, which I suspect is a similar recipe. Edited in an attempt to override the default center justification of text

Back in February of 2014 I presented test results of two purge products, SeaKlear System Flush and Unique Solutions Ahh-Some. The motivation for this experiment was (1) to cure a known-bad water problem, of which I presumed (and later verified) to be caused by biofilms shipped in my new spa, and to (2) compare these two products effectiveness. This original thread is found here: http://www.poolspaforum.com/forum/index.php?showtopic=45727 The important result of this experiment is that SeaKlear did in fact produce a visual result, at least when applied to my bad water, but that Ahh-Some was able to pull a great deal more material from the spa itself that the SeaKlear did not touch. The purpose of the present post is to summarize a new experiment which I recently completed, during which I compared three other products to Ahh-Some. Given that my working hypothesis would remain the same, (namely that Ahh-some releases material that others do not), my experimental method remained the same as well I would test with the competing product first, and then follow with Ahh-Some. If Ahh-Some released more material after another product had done its work I would declare the hypothesis valid. If Ahh-Some did not produce any more material than the others, I would declare the hypothesis invalid and the Ahh-some claims to be false. The present experiment, however, was conducted under different conditions. This time, in addition to testing products, I would be able answer this question: Can biofilms form even under ideal maintenance conditions with crystal clear water and no unusual sanitizer demand? To conduct this experiment required many hours, thousands of gallons of water, patience and a lot of work, but it paid off with a clear result. I will not present all the details I have documented, as this would consume some 25 pages including photos. Instead I will summarize my test steps, the results obtained, and conclusions reached. Note that except for the first product tested (Clean Start), all purges were performed on new, fresh water fill, heated and balanced to the same parameters. The products were tested in the order listed. I will describe the experiments themselves in a reply to this post Edited in attempt to override the annoying center justification

Your welcome. I'm about to share some additional results of a month-long experiment I have just concluded, where I compared three additional products with ahh-some. I'll share my test details later, but the bottom line is that ahh-some blows the others out of the water. In addition to the System Flush experiment, above, I now have data on Silk Balance "Clean Start", Aquafinesse "Spa Clean" and Natural Chemistry "Spa Purge" The evidence is just overwhelming.

update on this experiment: Since flushing the spa with Ahh-some last Winter, my water maintenance has been a breeze. My ozone generator maintains 1-2 PPM bromine with no bather load (bromide salts present in the water) and my sanitizer demand is unbelievably low. $6 worth of Ahh-Some has released additional material that $30 worth of SeaKlear did not touch. (Edit: I corrected the cost of Ahh-some and added the cost of SeaKlear)

FYI Ozone and Bromine is a beautiful thing. I have sufficient sodium bromide salts in my water (from initial fill treatment), I do not use bromine tabs or a floater, and my corona discharge ozone generator maintains approximately 1-2 ppm bromine in my spa indefinitely, under no load conditions (i.e. vacation) To keep up with bather load I use Clorox 8.25% bleach as the oxidizer.

makes sense. I just noted that nitro's decon procedure included an enzyme purge step as well, prior to the 50ppm FC dose. the implication, then, is that these enzyme based materials are not really biofilm removal products at all, at least not to the extent as the ahh-some product appears to be. There's probably still some confusion around what a "biofilm removal" product is.

yes my experimentation has certainly revealed better results with ahh-some compared to Seaklear system flush and I'm using ahh-some exclusively now and highly recommend it. I'm even tempted to perform additional experiments with other products in the same way I compared System Flush with Ahh-some and post results. I did suspect the crypto risk was low for residential hot tubs, after reading the CDC site, so thanks for that information, esp. that this guy does not grow/multiply in the tub. That is really good to know. But this raises the question regarding the decontamination recipe of 50ppm FC for 60 min (3000 ppm-minutes). AT 77 degrees F, this is clearly not enough to handle Crypto (which requires over five times that figure). However, 3,000 ppm-minutes is more than 60 times the exposure required to kill Giardia, which the CDC lists as the next most chlorine tolerant bug associated with hot tubs. Accordingly, 50 ppm for 60 min seems like an overkill of grand proportions to me, suggesting that I must be missing something regarding how the 3,000 ppm-minute figure was obtained. I'll study the link you posted to see if there is a clear answer

I'm seeing recommendations here for decon procedures involving 50 ppm for 60 min. other procedures (one I obtained from my local spa store for example) recommend 100ppm for similar time periods. I was just reading on the US CDC site where I found some very interesting information involving kill concentrations, which are expressed in terms of "ppm times minutes", or the product of FC concentration in PPM times the number of exposure minutes. http://www.cdc.gov/healthywater/swimming/pools/chlorine-disinfection-timetable.html The most chlorine resistant parasite, Cryptosporidium (or Crypto) requires some very aggressive treatment: 1ppm for 15,300 minutes (almost 11 days) 20ppm for 765 minutes (12.75 hours) 50ppm for 306 minutes (5.1 hours) 100 ppm for 153 minutes (2.55 hours) Of course, these numbers assume pH is 7.5 or lower, water temp is 77 degrees F or higher, and NO STABILIZER. these thoughts immediately come to mind: 1. it is now clear to me why, if if is really needed, one must perform superchlorinization AFTER and IN ADDITION to any purge or scrub process, as these procedures are normally performed on "old" water (read: stabilizer present). especially if one is concerned about crypto. 2. How does the higher water temperature of 100 degrees (for example) affect the above kill rates, such that one can de-rate the above CDC numbers? In other words, is 50ppm for 60min really enough to kill Crypto in 100 degree water? on a more technical note -- how does one derive such a extrapolation? 4. we know (see below) that legionella can find protective refuge in biofilms, and this implies that superchlorinating without purging first may not even be effective in some situations -- at least in the case of legionella. Are there other microorganisms besides legionella that can find protection from chlorine inside biofilms? 5. Do we know what the kill concentration (FC PPM times minutes) required for legionella is (assuming biofilms are purged)? http://www.cdc.gov/healthywater/pdf/swimming/pools/hyperchlorination-to-kill-cryptosporidium.pdf http://www.cdc.gov/legionella/downloads/hot-tub-disinfection.pdf

thank you for that explanation its making more and more sense. Your explanation confirms what I am seeing now, which is that after a couple of weeks of dichlor as the oxidider my pH rise is no longer an issue and I'm back up the 50pm TA to keep the pH from falling. What you are implying is that once I switch over to bleach (which is due soon), the pH drop will become even less of an issue and I won't have to add as much soda over time. So as a conclusion to my pH rise, which initially caused me to drop TA to 30ppm (due to heavy aeration): I would say this condition was quite temporary in the sense that after a few soaks and dichlor as the oxidizer things are stable now at more reasonable TA levels. Moreover, my ozone generator (after cleansing the spa with ahh-some) now is able to maintain a residual of about 1.5ppm bromine with no bather load and no added oxidizer. Basically I'm using a "two-step bromine, dichlor then switch to bleach, with borates" chemistry, which I may summarize in a separate post unless that would be redundant. things are going very well: My starting numbers were TA=50, CA=140.

ok I'm going to have to ask some more questions to make sure I'm following. thank you for that in depth analysis! What I get from the above is essentially: "When you add bleach the pH rises" BUT "oxidizing bather waste ... is an acidic process" THEREFORE "The net effect of addition and consumption/usage of bromine is pH neutral" However, "Dichlor is net acidic so it WILL drop the TA". why is this? is it because of the CYA? Is it true, then, that the net effect of addition and consumption/usage of bromine is net acidic when dichlor is used as the oxidizer but pH neutral when bleach is used as the oxidizer? Also I think you are calling out that the answer to this question: (dlleno asked:) "I'm adding net acidic things: dichlor itself, but won't the conversion to hypobromous acid via the bromide bank exert even a stronger downward pull onto pH?" is essentially this: No - when you add dichlor, the net pH effect is no different whether there is a bromide bank present or not" Also help me understand the conventional spa store wisdom: Why do they tell us that hypobromous acid is a "stronger" acid than hypchlorous acid and therefore the use of bromine will be net acidic compared to chlorine?

ok good; thanks. yes I'm adding net acidic things: dichlor itself, but won't the conversion to hypobromous acid via the bromide bank exert even a stronger downward pull onto pH? I keep the spa at 4-6ppm, but when away for several days the ozone generator is able to keep about 1 or 1.5 ppm bromine now. yay for ahh-some. Since starting out at TA=50ppm I have added four teaspoons of dry acid to keep pH below 8.0. this drove my TA down to 30ppm or maybe 35 (granularity below increments of 10ppm is difficult). over the last 1-2 weeks my pH has settled down to 7.4, so I added a tablespoon of Soda, and that brought TA back up to 40ppm. hope this means I can start to build up TA to more comfortable levels. yes my jets are many and all use air injection. I do have a full time ozone generator as well, so lots of aeration happening.

just a quick comment on my experience here. I have added 50ppm Borates via boric acid from Duda.. I started with 50ppm TA (made this adjustment first before adding the BA). the only surprise to me is that in order to keep pH rise under control I have to target a higher value (i.e. 7.6--7.8) and run with TA = 30ppm. yea thirty parts per million total alkalinity, which sounds a little scary. but I'm watching it carefully and so far so good. FYI my CA is 140. Water is still "young" in that I haven't yet switched to bleach

I can confirm this from personal experience. after treating with Ahh-some my 24 hour Chlorine demand is on the order of 10% with ozone off and water temp 80 degrees. and I didn't even super-chlorinate - just standard shock treatment to 10ppm FC after the flush. I'm becoming more and more impressed with the need to flush with an ahh-some like product and plan to do this more than just once. BTW I happen to have tested SeaKlear against Ahh-some and found the latter to be superior. proof of the pudding was the material removed by ahh-some that SeaKlear did not remove. I tested 24 hr FC demand with Taylor FAS-DPD drop test. I have now eliminated my mysterious Bromine demand which my ozone system was unable to keep up with (sodium bromide bank present).

Indeed, that would have been a good confirmation, to be sure. however, the fact that the second application of system flush produced no new material confirms that the first application had done its work and reached the limit of its effectiveness. It was only after confirming this point, that the ahh-some product was added and found to dislodge more material. Now then, in order to conclude from this test alone that ahh-some is a better product, one would need to assume the following: 1. the measure of success is the amount of material accumulated in the vessel after treatment. This is an easy assumption to accept. 2. there is only one "type" of gunk that these products are removing. This one hasn't been confirmed, so its best not to jump to this conclusion. . For example, the "gunk" in my spa had accumulated over a period of only 6 months, over two fills starting with a brand new spa. Therefore, although I would have expected the first fill to purge such material, it is conceivable that this gunk would have contained more mfg adhesives from labels, for example, assembly debris, etc, compared to an older spa. Was the ahh-some product simply more effective against the "type" of gunk in my spa that SeaKlear couldn't touch, and would the converse then be true as well? that cannot be determined from my test. One test that is yet to come is the sanitizer demand test -- to see if my ozone generator can oxidize enough sodium bromide to keep the water sanitized when not in use. FYI I purposely did not perform a superchlorinization step because I wanted to see if I could assign the root cause of my problem statement to the gunk itself. my other conclusion is that I'm going to repeat the ahh-some treatment at the next fill. maybe even every fill.

Oh... Yes good point. I should have noted that the gunk started to accumulate before I dumped the filters in. Overall very impressed with Ahh some.

Here I present results from testing the "Ahh-some" flush product against SeaKlear's "Spa system flush". bottom line: Ahh-some is the clear winner for me, and I won't go near the System Flush stuff anymore -- but read on for specific details. My tub is a good candidate for a flush: Brand new late last summer, its 2nd fill is ready to dump. My ozone generator cannot oxidize enough bromide (from the bank) to keep up with the sanitizer demand when the spa is not in use (proper dosing for bather loads has been followed). My water is always clear; there are no other problems other than this curious sanitizer demand. At this point I do not suspect the ozone generator itself to be at fault, although that is a stone I may have to turn over. In my experiment, I set out to prove (or disprove) the hypothesis that Ahh-some is a better biofilm flush product. While unable to test the ability of either product to remove and kill bacteria, my test indicator would be the amount and nature of the gunk deposited along the water line. Starting with the stated hypothesis, my plan was to clean my spa with System Flush first, and then follow with Ahh-some. in order for the test to be meaningful, I would flush with SeaKlear system flush twice, following the label directions. here are the results. Background detail -- spa water is ready to dump, but balanced and still crystal clear. I soaked first for about 30 min at a relatively high concentration of bromine ~8ppm; then got out and started the flush process. Here are the steps I followed and the results: 1. I Removed the filters (put them in filter cleaner to soak) and Dumped the entire bottle of SeaKlear Spa System Flush into my 500 gal spa (This is the dosing recommended for an 800 gallon spa). per label directions, I ran all jets and water features for about 45 min. air intakes were turned down to minimize foam. The result was a nasty dark brown deposit along the water line, which appeared almost immediately. I let her sit all night. The next day I shut her down, drained, cleaned, and refilled. 2. I then repeated the same process with a second $15 bottle of System Flush. This time I got all white foam and no residue along the waterline. per label directions (filters still out) I let her sit all night. the next day I shut her down, drained, cleaned and refilled. 3. Now it was time for the ahh-some treatment. This time, to avoid confusion with metal deposits I treated with a metal sequestrant. I then took a level tablespoon of Ahh-some gel (dosing recommended for a 300 gal spa) and introduced it to the water. I found the gel was rather resistant to dissolving in the water but suspected that was because my water was 55 degrees... but it started working right away. per label directions I put my filters inside the spa to decon them as well**. Also per label directions I dosed with enough chlorine to be effective (10ppm). I ran the jets 30 min. Immediately, a nasty brown gunk appeared, this time a little lighter in color but easily twice as much material ended up along the water line, compared to the first System Flush treatment. 4. After an hour, I shut her down drained, cleaned, and refilled. I hosed the filters down and re-installed. , shock to 10ppm chlorine (I did not superclorinate) and I'm now in the process of reducing TA to 50ppm. Some things to note (and to like) about the ahh-some product * two significantly over-dosed System Flush appliations did not even come close to the amount of material removed by a single under-dosed application of ahh-some. * This material is more than a "dislodge the gunk" product. while it does that very well, it also claims to kill bacteria. otherwise they wouldn't recommend putting your filters into the tub as well * sanitizer is required to work with the ahh-some product. I'm going to look into this further, but its not clear to me what FC levels would be best. Next steps for me: * After converting to bromine, see if the spa will maintain a low residual bromine level when not in use. * I may start using this stuff at every drain, or perhaps every other drain. it could be overkill, as a great many of us survived the 80s and 90s without this stuff, but consider this: whatever gunk you see on the water line after treatment is no longer serving as a culture medium down inside your pipes. ** Edit for additional clarity: I haven't changed any of the above text, but what I didn't state clearly is that the brown gunk formed immediately on the vessel walls, and THEN I put my filters in to be cleaned. The ahh-some did release material from the filters, but before adding the filters I proved sufficiently that ahh-some removed more material that the SeaKlear did not touch.