[Music] hi welcome to the pool guy podcast show today i'll be joined by bob lowery who is a premier expert in chemistry in the pool industry and we're going to go over algaecides and the best way to fight and prevent algae in your pool pool service pro open a leslie's wholesale account today and receive wholesale pricing on products you use every day leslie's pool supply offers convenient locations that are open seven days a week another great benefit of opening a leslie's wholesale account is leslie's referral program get referred to a customer looking for weekly pool service also receive priority service enhanced rebate programs a discount on your general liability insurance through spa a discount on your pool writing software through skimmer and an opportunity to co-brand with leslie's on your social media website truck and more save time and money and grow your pool service route and become a leslie's pro so i'm joined again by bob lowery and of course if you don't know who bob lowery is he's the premier chemistry expert in the pool industry how are you doing this morning bob doing great uh glad to see you all from lima peru today we could list your accomplishments it would take probably about most of the podcast here you know you want to briefly just go over some of the highlights in maybe a minute or so so people can get an idea of where you're coming from well i've been a chemist in the swimming pool industry for 48 years during that time i've owned two chemical companies and a publishing company i've written 21 books and i've developed 111 chemicals and i've written about 30 white papers about 15 or or 20 technical bulletins i've bothered to to learn about this how chemicals go in water spent my life doing it and now i'm i'm gladly giving that information back to homeowners or service techs or tool stores or anybody that will listen i'm an independent chemist and therefore the information that i give is my best opinion without regard to who makes it yeah that's with that said i think we really appreciate your time when you give us misinformation because you're you're a reliable source and i think some of the questions that i get asked all the time i just put them in these podcasts so that people can get the answers and there's one coming up here from someone just a couple days ago but we'll jump in here and we'll talk about pool algaecides and the first question is do you actually need an algaecide to treat algae in a pool well need is one of those definable words i guess you might say you know what's the definition of need my first my first choice when it comes to algae is to just use chlorine you already probably have it on your truck you've probably got some liquid chlorine on your truck or at least you can get some without much of a problem and i would try that but the problem is that most people don't add enough chlorine to really get rid of the algae and that's where a process that was probably started by the folks over at trouble free pools they have a website called trouble free fools and they have a process they call slam and i've been recommending this for years but they have a formal program what the essence of the program is to add a large amount of chlorine to the pool and then maintain that level for 24 to 48 hours and most people want don't want to maintain it for that long and therefore they get a you know not a complete kill so this method on their website is called slam shock level and maintain and i just call it a a hyperchlorination method and what you do is you add 25 parts per million of chlorine or 40 of cyanuric acid whichever is a greater amount and you add that to the pool and then you need a a method of measuring chlorine that will measure 25 or 30 or 35 parts per million of chlorine which is called an fas dpd test kit and it's a drop count or a titration and uh it will go up to 50 or 60 parts per million but anyway it does it one drop at a time and it's equal to one part or half a part per million so at any rate we add this amount of chlorine to the pool we leave the pump on we brush the pool and then in the beginning we check the chlorine level maybe once every hour or two and see if it's going down when it goes down by three or three to five parts per million then you add some more chlorine to get it back up to where you started and then you keep doing that until you get only a 1 ppm change from night to morning or overnight so if you're using 25 parts per million of chlorine you check it in the morning if it's 24 parts per million then everything's dead you only lost one part per million overnight but if you check it in the morning and it's 15 you haven't killed everything so you need to maintain that level long enough to where there's no change in a 10 to 12 hour period and then you've killed everything um and it's difficult to do this method when the cyanuric acid level is above 100 because then you're looking at 40 parts per liter chlorine so you could just drain some of the water fill it back up and now you and you could add 20 or 25 parts per million of chlorine and be good so um that's the number one method and then you can start looking at algaecides if for some reason that doesn't work or for some reason you don't want to do that method you can add an algaecide and probably the the best algaecide is a copper-based algae copper-based algaecides have two real problems one is you need enough to kill the algae but if you get too much you can cause a stain many of the manufacturers use a a sequestering agent in with the copper so when you put it in the pool even though you're at a higher level of copper it won't cause any stain um that's the method but it's not instant so you don't put it in today and come back tomorrow and all your algae is gone it doesn't work that way if as you as you might imagine um algae mature and colonize and then they want to protect themselves so they secrete a a polysaccharide slime layer over top of themselves which is kind of like a dome and then they have the wall of the pool behind them so there are sconced in this little you know in this little domed area and this is what the algaecide or the chlorine has to break through to kill the algae and and this is the reason that we recommend that you brush the pool because when you brush the pool you break up that dome and and it allows the chlorine and algaecide to get into the algae and kill it just a reminder that when you've got algae you really do need to brush and twice a day as a recommended level regardless of whether you use them which algaecide you're using the other metallic algaecides are silver and there are silver based algaecides they do a fair job too the problem is that copper doesn't kill algae very quickly and so it's not instant like chlorine is so you do need to give it enough time to work you also need to make sure that you've got a it works better when the alkalinity is a little bit high and the ph is a little bit low so it actually works better under those conditions so when you're going to use a copper algaecide i would probably shock to maybe 5 or 10 parts per million of fluorine first and then a day or so later put the copper in that way the algaecide or the algae itself are a little bit shocked from having so much chlorine and they're vulnerable then to the to the copper-based algae you do the same thing with silver the danger with silver is that you oxidize the silver and make silver oxide which is the same stuff that's on the old 35 millimeter black and white negatives that is silver oxide so at any rate you run the risk of perhaps causing a stain if you get too much chlorine in there with the silver and then of course there are what are called poly quads and these are polymers that are a mixture of a polymer and a quaternary amine compound and they are pretty good but they do function a little bit as a clarifier the polymer part of their their structure is similar to a polymer like we use for clarifying water and so we can end up having that product actually work like a clarifier and end up in the filter which is not where the algae is the algae's in the pool so um there is a possibility of doing that but they are good and they are good at preventing algae long-term so um they're good as a long-term algaecide and i think finally we have what are called quat algaecides and many of these algaecides um they dilute them down quite a bit and sell them as a cheap algaecide where you can buy a gallon for ten dollars or something like that you know a lot of times a court of algaecide will cost from 15 to 25 and you can buy a gallon for 10 or 15 it seems like a bargain but it's actually just very dilute uh either copper or polyquad algaecide the danger with a quad algaecide is that if you use it a few times or a couple of times it's very close to being a surfactant and as a result if you use it you can't get some foaming in the pool i'm not sure if that's the whole gamut of algaecides but i think it is and you can get most of them there bob um just real quick back to the slam method that you mentioned i think for the pool pro it's harder for us to do that method because you'd have to go back to the account a few times during that day and you know we really can't return usually until the next day on that method so i i do what i call shock and awe or i'll put in 50 parts per million of chlorine in the pool and then by the next day when i go back there usually it holds pretty well so we kind of have to modify that a little bit put a little bit more chlorine in that way we don't have to keep measuring it every couple hours because we can't really do that and i think that's why a lot of us rely on the altra sides also because that kind of helps speed things up in a way i guess without having to kind of monitor it like that but for a homeowner the slam process is highly effective if you look at the thread at the trouble-free pool site people have really great success with that method and i agree that it works really effectively you're right for a service tech and perhaps uh you know going up to to uh 50 of the of the cyanuric acid level uh is is maybe a good method so maybe using 50 bars per million of chlorine is a you know maybe double or a little less than than what i would recommend than what i was recommending but um you know 15 come back the next day i would guess though from a working standpoint if you put in 50 and you come back the next day and there's there's less than 30 parts per million left in the pool you probably need to go back up to 50 and do it again yeah it happens a lot too where you come back the next day and it's you know under under three parts per million and sometimes it's even at zero because sometimes we deal with pools that are extremely neglected that more than likely probably need to be drained versus you know cleared up with chemicals but here in california draining a pool in fact i just heard yesterday that we're probably to be under another drought this year and there's going to be a lot of restrictions i know northern california already implemented some and so draining a pool in some areas just is not something that can be done and so chemical wise is kind of how we do it by just shocking it and um in your opinion is it can you you know turn a pool around that's been green for a long time which is chemicals or is it better off just draining that pool no you can do it chemically but you have to realize that that when you do it chemically you may you may be increasing something in the pool and have to add something else so ultimately you're going to be increasing tds and perhaps some of the other things so tds is not such a great thing as far as you know you're not going to increase it so much that you need to drain it right away because there's a lot of leeway with tds but i think i think you can do it successfully and of course you can flock the pool with alum um and it gets rid of some algae that's floating in the pool but it also gets rid of some other things in the water where guys like rudy are claiming that that by adding that you can lower cyanuric acid and phosphates and things like that and so it's possible that we can use some alum and uh get rid of some of this stuff in water and then when we vacuum the waste we're only using a you know losing an inch or two of water from the pool and replacing that but we are lowering some of the other things that are in water um tds and and cyanuric acid and the pool will function better when we get rid of some of that stuff i guess the other question is the use of sodium bromide i know you didn't mention that when you were talking about the algaecides but yeah i didn't i just wasn't an on purpose thing and i'm glad you brought that up um sodium bromide um is an effective algaecide and many of these products are labeled as yellow something um the original product out there had a patent on it was called yellow tree i'm sorry yellow sorry yellow out there there's a bunch of other yellow stop yellow tree yellow tree you know they're all yellow something and the idea was it would stop yellow algae but the original one i think was was yellow out at any rate that one was had a pandemonium salt base and the rest of the products because the first one had a patent on it the rest of the products have sodium bromide in it and sodium bromide algaecides are affected but you must understand that when you add any amount of bromide to the pool that bromide is in the water as a bromide ion and when the ion is in water when you add an oxidizer to the water it it changes the bromide ion into hyperbolas acid which is like hypochlorous acid and then it becomes a sanitizer and it destroys things and then it goes back to being a bromide ion just like chlorine in water is hypochlorous acid when it's all finished being hypochlorous acid it goes to being chloride so same idea except that when you add chlorine or any other oxidizer to the pool bromide gets reactivated to hyperchromos acid and that means if you've added uh many of these products uh sodium bromide products you are actually adding about five parts per million of bromide to the water and this means that up to five parts per million of chlorine gets converted into five parts per million of bromine so you no longer have a chlorine tool you have a bromine a bromine pool and you may not even know it and and the reason that this is important to understand is that the bromide doesn't go away so when you add chlorine it makes hyperbolic acid it makes bromide and the next time you add chlorine it does the same thing so it continues to do that forever until the bromide is gone and the bromide only gets reduced when there's a water loss and it can get reduced when bromide makes a a compound that doesn't go back to bromide so it can make a a bromochloroamine or bromochloro ammonium then it takes it out of the out of the system but for the most part the bromide is there and you've got a bromine pool and it doesn't go away and bromide is not protected by from sunlight degradation bromide is used up at the rate of 65 in two hours and so you lose all of the chlorine level or all the bromine level in about five hours it's important that you know that and it's also important to know if you've got a bromine pool instead of two to four parts per million of chlorine you actually need four to six parts per million of bromine and you need a bromine test kit um you need to be aware that if you use a bromide product this can happen and i am not trying to spread a rumor but i have heard uh from the phta that epa is considering uh outlawing sodium bromide algaecide i've heard the same thing too to the grapevine different sources have told me the same thing that for a number of reasons they're considering that and i think so i think manufactures already starting to taper back on some of the sodium bromide products ahead of time just like with them the big reason is this that when you when you put bromine in water you run the possibility of making bromate and bromates are cancer-causing and that's the reason that epa looks at it is there's a possibility that you can make be making bromates in your pool it's not such a big problem in spots it is a problem in spas that if they put sodium bromide in the spa and then use an ozonator that makes bromate and that is cancer-causing but um spas are mostly covered and so we don't have sunlight in them but when you have bromide in water it can make bromate from sunlight and bromates are bad and so i think that's probably why epa is looking at it and ultimately it's going to be gone so those are some reasons not to use it but if you are using it that's the awareness and i think another another thing that i should mention is that i was talking to the people over at natural chemistry they make their phosphate remover and i was bringing this point up is that i've done tests where i had algae in a spa and i'll pour the phosphate remover directly into the spa and then within a few minutes the algae is gone but the phosphate remover is not technically ep algaecide so how does but how does it work in removing the algae from the pool then in that in that respect okay the algae as you might guess have to reproduce pretty quick because they're they're you know usually single cell and so they have to multiply quickly to to replicate and reproduce themselves and so the main nutrient of uh algae is phosphates and so if there's phosphate around that's their main food source so they look at at their main food source and if you remove phosphate you have taken away their main source of food now they still do need carbon because they are carbon based plants and they need sunlight but um there's there's other things in the water that they can use the you can't get rid of the carbon in the pool that's impossible because you've got carbonates bicarbonates carbonic acid and co2 in the water so there's plenty of carbon form that's for photosynthesis that's not as a nutrient phosphates are number one number two is probably uh nitrates and then sulfates and there may be some sulfates in the water certain products have sulfate in them and so when you use them you increase the sulfate level and then you can't have an algae problem because it's feeding on the sulfate and as you might guess from the name potassium mono per sulfate mps non-chlorine shock has sulfate in it but at any rate phosphate is something that we don't want to get the level too high if you ask the manufacturers they're going to tell you it's you know 200 500 something like that is the maximum i think that probably you don't need to worry about them until they're i don't know 1500 maybe 2 000 and if you're going to use borate in the pool which i know we're getting a little off topic but if you use borate in the pool which is an algae stat instead of an algaecide you probably don't need to remove the phosphate at all because it prevents the algae even if you have phosphate in there if you've killed the algae and then the the borate prevents it you don't need a phosphate remover because there's no algae being we're talking about algaecides but what would be the best way to prevent algae in the first place i know that we talked many times before about balancing the pool water and that's a key factor a lot of homeowners and pool pros still deal with algae on a regular basis for a number of reasons i mean rudy just has a new book out about that which i think is really well done as far as pointing out some of the environmental factors that cause algae but besides those points what would be like some of the key takeaways in some ways to prevent the algae from even forming in the first place and you mentioned borates and we can touch on that more too one of the things that that i researched and the advantage i have as an independent chemist is that that owning my own company and being independently wealthy i can go and spend a thousand hours doing something and i don't have a boss telling me i'm wasting my time or you know don't do that we're not going to make any money from that or whatever so i can go research something until i'm satisfied to have all the information and one of the things i did about eight years ago was i started studying how much chlorine we need in the water to kill them and recognizing that algae are are harder to kill than bacteria so in a residential pool and we are talking residential in a residential pool i found out that most everybody agreed that that somewhere between .03 and .05 parts per million hocl hypochlorous acid kills algae and some people disagree with the 0.3.03 and other people say 0.05 so in the process of finding that out i did everybody that i talked to or listened to or read about would agree that .05 would kill algae 0.03 maybe maybe not so um to be sure that we killed it i settled on 0.05 we can actually calculate how much chlorine is in the pool and and the calculation goes like this when you have more than 30 parts per million of cyanuric acid in the pool 97 of the chlorine is bound to cyanuric acid and this only leaves three percent so there's only three percent of the chlorine in the pool at any time that's doing anything and then three percent is in equilibrium within 97 so as some of the three percent gets used it gets replaced from the 97 and it keeps maintaining that 97 and 3 until there's no more chlorine left in the pool so it maintains that so we know that there's only three percent of the chlorine in the pool we also know that at a ph of seven five fifty percent of the chlorine is hocl and fifty percent is ocl minus from that we can determine that the amount of hocl in any pool is only 1.5 okay so now that we have 1.5 and we know we need 0.05 parts per million let's multiply two parts per million times 1.5 percent and what that gives us is .03 and that's not enough chlorine to kill algae it's not so now let's do three parts per million of chlorine three parts per meter chlorine times one point five percent is point zero four that's almost enough to kill algae it's only five thousands away from killing algae so it's it it probably would kill out and if we do four parts per million four parts per million tons one point five percent is point zero six and that will kill algae so we can actually calculate how much chlorine it takes to kill algae i think the problem though bob is when the cyanuric acid level then is at a hundred then what kind of chlorine level do we need to keep well and this is this is i was going to take the next step further rather than homeowners doing that calculation we have determined that if you use a chlorine level that is 7.5 of the cyanuric acid level you will always have enough chlorine in the pool to prevent and kill algae so if that that can become your minimum and that's really great we now have a method of determining how much chlorine you need in your pool and and yes you're right um i know what you're thinking well what if i have 100 parts per million of cyanuric acid technically you need 7.5 parts per million chlorine to prevent algae and if you're only chlorinating at two to four parts per million of chlorine you don't have enough chlorine in the pool that's why you get algae and so the thing to do is lower the chlorine level and then take 7.5 percent of 50 and that comes up to 3.75 so you need almost four parts per million chlorine in the pool not two but four to keep algae from coming and and i'll take it one step farther because we teach this in our in our institute in our books if you add bori to the pool at 50 parts per million then you use five percent of cyanuric acid instead of 7.5 so now you need a chlorine level it's five percent of cya and even if you've got uh 80 parts per million of cya you still only need four parts per million flooring so a pool with a hundred parts a million of cyanuric acid if you add borates to 50 parts per million you would just need five percent five parts per month but that's the minimum and if you're trying to run the pool at two even though people say oh my god two is a big amount if you're running the pool at two you run the risk of getting algae you don't have enough chlorine in the killing form yeah so so for the pool pros out there that have pools that are 100 parts a million or 150 parts a million i think one of the things they're battling is that every week they're getting algae in there and they're scratching their heads thinking well the chlorine level is high it's five parts a million or whatever but as you're saying here that wouldn't be enough to kill algae i mean it's chlorine in the water but at that level of cyanic acid you're going to have an algae problem no matter what unless you raise it even at five parts per million you still don't have enough chlorine to kill the algae yeah so you know you and then you kill it and then it's gone for a while and because you're under chlorinating you come back to the same thing and you think i okay i'm getting recurring algae how come you're not you're just not ever keeping enough chlorine in the pool to keep the algae away one of the things that you can do with regard to algaecides you know we talk about use whatever you want to do use the slam use a high level of glory use a hyperchlorination use copper whatever when the algae is gone put in boring if you put borate in algae doesn't get started after that and that's the advantage is that you put that in the pool and it prevents algae from getting started it's not an algaecide so if you've got algae growing in the pool is not going to kill it but if you put it in the water with no algae in it you're not going to get any algae coming in we had a guy that was in one of our classes said he had 70 of his pools with a chlorine generator on and he was running his pools at 70 parts per million of boring he said the day after he was at this pool the chlorine generator stopped working he came back six days later in southern california came back six days later and no algae in the pool because he's got 70 parts per million of boredom that's pretty amazing i've mentioned that before my test here on my own pool where i've left with with three weeks of no chlorine of course i wasn't swimming in it and i had the borate level of 50 parts per million and there was no algae at all for that three week period and then just as a side note you know just recently um i got a salt system from my dad in indio california and i told him to put the borates in his pool he just drained it refilled it put the salt system on and um he's having trouble he was having trouble all week long trying to get the salt system to work getting the salt level right and with the borings in there 50 parts a million i told him don't worry about it just keep working at it and for a whole week at 90 degree weather in india he had no chlorine in the pool and had no algae and he was just trying to modulate that salt system and so it's highly effective i mean i just it's amazing actually when you think about it how effective it is yeah it's great stuff and and i think literally every pool should have it in there but and believe me i don't make any money if you put a board in your pool or not i don't make a penny if you do it so it's just good advice i think it's a great chemical well well in here with that and then i think that was a great proper analogy for anyone listening and i think the takeaway here is that the chlorine level needs to be 7.5 percent of the cyanuric acid to be effective and i think that's one part of the equation that a lot of people are missing when they're trying to treat algae in the pool they're wondering they're wondering why it's not going away because the chlorine level seems good to them but in actuality it's not good enough based on a cyanic acid level so i think that's that's key to the fighting algae so i hope you found this podcast helpful and i hope you can tune in for the other episodes that i recorded in this series i'm going to talk to bob lowery about using boring senior pool and some of the benefits and the fact that it's not a magic bullet in the next podcast we're going to touch on a pool with the leak we're also going to cover total dissolved solids or tds in the last two podcast episodes and if you're looking for the episodes in this series you can of course look at the links in the description i'll have all of them listed there or go to my website swimmingpoollearning.com and on the banner click on the podcast icon that'll take you to a drop down list of the podcasts episodes that i recorded with bob lowery and also the other podcast that i recorded here with over 600 different podcasts you can definitely find a recording that's going to be interesting at the time you're gonna need it or if you're looking for certain information i'll probably have a podcast on that subject and if you're in the industry and you're looking to enhance your business definitely check out my coaching program at poolgatecoaching.com that are great benefits for joining there again you can learn more at coolguycoaching.com thanks for listening to this podcast have a great rest of your week god bless pool service pro open a leslie's wholesale account today and receive wholesale pricing on products you use every day leslie's pool supply offers convenient locations that are open seven days a week another great benefit of opening a leslie's wholesale account is leslie's referral program get referred to a customer looking for weekly pool service save time and money and grow your pool service route and become a leslie's pro you