Well the spa is never exposed to direct sunlight which I read is why you need cya. And my manual says fc should always be between 2-4ppm.
Constant daily low free chlorine!!!
- Thread starter mrdorkdar
- Start date
Well the spa is never exposed to direct sunlight which I read is why you need cya. And my manual says fc should always be between 2-4ppm.
- May 3, 2014
- 58,451
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
You need some CYA in all pool/spa water to temper the harshness of the chlorine. Indoor pools are suggested to have 20-30 ppm. Residential. The public side has not come up to speed on that and that is why public pools are harsh and stink.
It is your spa, but some CYA in the water will make the water much more enjoyable.
It is your spa, but some CYA in the water will make the water much more enjoyable.
- May 3, 2014
- 58,451
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
It is most likely due to biofilm in your spa plumbing that is full of bacteria that is consuming your chlorine. Also without CYA your loss of FC is accelerated.
You are essentially doing an Overnight Chlorine Loss Test. With that loss, you have something consuming it.
Consider getting some Ahh-some and purging your spa.
Take care.
You are essentially doing an Overnight Chlorine Loss Test. With that loss, you have something consuming it.
Consider getting some Ahh-some and purging your spa.
Take care.
is it ok to sit in these spas for 1.5 hours or so without showering beforehand? Is that too much on the water and maybe what is leading to biofilm?
It's a factor, but if the sanitizer loss is new and you haven't changed your hygiene practices then you really really need to go back to my original recommendation and purge with ahh some until you achieve the criteria I mentioned. I have tested several purge products and my assessment is that your purge was not effective. I remain at a loss as to why you haven't taken this advice seriously. I don't mean to be harsh but I think you need to revisit the recommendations here to purge with ahh some
In case anyone wants too see my experimental white paper results and conclusions re biofilms, I have exposed my blog posts here
Zenfolio | Photos by Boise Diesel | Controling biofilms in spas and hot tubs - PART 1
Zenfolio | Photos by Boise Diesel | Controling biofilms in spas and hot tubs - PART 1
Oh I totally will take your advice. I am new to this and to be honest I get a bit of different advice based on who I talk to. This spa is less than 2 months old, and the water in it this time is less than 1 month old. I just don’t get how the water and plumbing can be so bad already.
i also just bought some different shock that is chlorinated this time, and added stabilizer. Just shocked the spa to 10ppm fc and added the stabilizer. Curious to see what the fc is tomorrow.
Oh man two months I was in your situation! Read my blog post... I admit it's a long read but you may find that you are in good company. mfgs and many others refuse to acknowledge biofilms in brand new spas
Trust me man you will save yourself many troubles if you do the ahh some thing. Get your chemistry down too by reading up on this site. The guys advising re cya know what they are talking about. I'm convinced at least with the info in hand, that you have a biofilm problem and that you may need to purge more than once with ahh some. Patience is the key .. biofilms are smart nasty neferious living organisms that in all likelihood were present in your spa from day 1.
Trust me man you will save yourself many troubles if you do the ahh some thing. Get your chemistry down too by reading up on this site. The guys advising re cya know what they are talking about. I'm convinced at least with the info in hand, that you have a biofilm problem and that you may need to purge more than once with ahh some. Patience is the key .. biofilms are smart nasty neferious living organisms that in all likelihood were present in your spa from day 1.
I realize there is a lot of focus in this thread on biofilms in the plumbing - and certainly this is probably the number one issue in hot tubs and water quality. But in my experience, ahh-some only does so much. The biofilms regrow back in just a few weeks. Maintaining good water quality, and not allowing FC to bottom out prolongs the regrowth, but, it's inevitable that they come back. It's just a matter of time. Keeping your filter clean is probably the most effective thing you can do.
Stabilizer absolutely slows down the loss of chlorine. Chlorine wants to be a gas. It does not want to stay in the water. The higher the level of Chlorine the faster it evaporates. The higher the temperature of the water the faster it evaporates.
With no CYA, and FC at 4ppm, the Chlorine is evaporating, and oxidizing your cover. It will not stay at 4ppm for very long no matter what you do.
How much stabilizer did you add?
Also note, Chlorine will oxidize CYA. It will disappear from your water over time. The rate in witch it will disappear depends on how hot your water is, and how high your chlorine levels are. It varys a lot from one tub to the next. For this reason, I recommend that you have a test kit for CYA, and test monthly until you establish a pattern, and are able to guess where you are at before you do the test. It has been three years for me, and CYA tests are still unguessable for me. I still test regularly. In my tub, CYA oxidizes about 1ppm per day. This is much higher than what others report here.
Stabilizer absolutely slows down the loss of chlorine. Chlorine wants to be a gas. It does not want to stay in the water. The higher the level of Chlorine the faster it evaporates. The higher the temperature of the water the faster it evaporates.
With no CYA, and FC at 4ppm, the Chlorine is evaporating, and oxidizing your cover. It will not stay at 4ppm for very long no matter what you do.
How much stabilizer did you add?
Also note, Chlorine will oxidize CYA. It will disappear from your water over time. The rate in witch it will disappear depends on how hot your water is, and how high your chlorine levels are. It varys a lot from one tub to the next. For this reason, I recommend that you have a test kit for CYA, and test monthly until you establish a pattern, and are able to guess where you are at before you do the test. It has been three years for me, and CYA tests are still unguessable for me. I still test regularly. In my tub, CYA oxidizes about 1ppm per day. This is much higher than what others report here.
This is absolutely true, which is why i advocate for regular purges, and to establish your own cadence based on usage and actual sanitizer decay rate and purge results. Biofilms have even been shown to survive in low levels of chlorine, and will regenerate quickly (I cite the literature for these conclusions in my blo post). in my own experience, and this is based on the results of thousands of gallons of water (experimenting), imy advice s to:
1. establish a baseline by purging multiple times with ahh-some until the product releases no new material. This means you have ahh-some laced water, filters in their normal positions, and the water is perfectly clean. this is not trival to achieve, but it can be done. Some even give up and blame the Ahh-some for introducing material itself! I've coached some through as many as 10 purges before they reach this milestone, but it is the only way to know if you have a clean spa. this will also give you the opportunity to know what a real sanitizer decay rate should be, given your own spa, your own chemistry program, and whatever conditions prevail.
2. start by purging every drain. that is so simple and so inexpensive -- just dose with ahh-some before you drain and see what material it releases. you will soon know, based on this result, whether you should continue to purge every time or perhaps every other time. extended drain intervals using the switch-to-bleach program will especially benefit from this. Note that just because ahh-some releases something doesn't mean it is releasing biofilms, but see my discussion of this point in my blog. Skin oils and other contaminants can become a food supply...
These steps allowed me to see that a bromine spa, properly dosed with sodium bromide and using a strong corona-discharge ozone generator, can actually maintain .5 to 1ppm FB by itself. the sanitizer level drops asymptotically and never reaches zero! you will not see that if there are biofilm growing in the water.
In this particular spa, it appears there is a very real CYA issue, to be sure, and the chemistry issue needs to be solved. what I am offering, however, is that Natural Chemistry is not an effective purge product, and that since the user experienced a sharp increase in sanitizer consumption this is evidence that biofilms are present, and the only way to establish a good baseline with certainty is to purge until you get no more release. Note that I purged with Natural Chemistry, plus a handful of other products, and THEN tried ahh-some , which released so much material I had to purge multiple times to get things clean. Thats when I saw the sanitizer decay rate optimized.
I acknowledge that many of us run hot tubs with some non-zero accumulation of biofilms, for the reasons you mentioned. In Fact, right now my own spa has reached the point where it cannot maintain non-zero bromine! this is why I advocate for regular purges.
Well I bought chlorinated shock, and tested my water this morning and it was only .4 fc. I added only the amount that was supposed to make 4ppm. Ran the circulation for 15 minutes, and ended up with 9ppm. What did I do wrong?!
Well the bottle said 1/2 oz for 500 gallons...so I put in a tablespoon and a half.
I assume you're using your drop test kit.
If you're using dichlor 3/4 of an oz would increase your level by 6.2 ppm. if you started with .4 ppm that would take up to almost 7. If it was trichlor it would increase by 10.
If you're using dichlor 3/4 of an oz would increase your level by 6.2 ppm. if you started with .4 ppm that would take up to almost 7. If it was trichlor it would increase by 10.
Chlor Brite. And I tested it with the Taylor dpd kit. Pretty sure I’m doing it right.
You may want to repeat the test and see what you get now. The difference between 7 and 10 isn't that much and could be accounted for by inaccurate testing before or after and or using heaping spoonfuls compared to level. If your new test results are the same just add less next time.
Using the pool calc to calculate the correct amount I came up with .4 oz to get to 4 ppm. That's about half of what you added (3/4 oz). Here is a link to the tool:
https://www.troublefreepool.com/calc.html
Using the pool calc to calculate the correct amount I came up with .4 oz to get to 4 ppm. That's about half of what you added (3/4 oz). Here is a link to the tool:
https://www.troublefreepool.com/calc.html
Ahhhh! I added a teaspoon and a half, not tablespoon. Sorry! But I still say I added the right amount of shock. So ya, I’m still stumped why it jumped to 9ppm from .4.