Chlorine Smell on skin

[Tonyf]

Our spa was new in October '07 and we were using Ez spa with DICHLOR. We ended up with cloudy water frequently as EZ Spa sems to lock up the chlorine and we were unable to get good chlorine readings.

We drained and had new water delivered three weeks ago and began using just dichlor with MPS shock initially on the fill up. We haven't been using the spa as much, but added 1 teasp after each use and the chlorine registers between 3ppm - 5ppm each time before my wife and I soak. When we get out, we have a small amount of chlorine smell on our skin.

I read in other posts that the smell is Combined chlorine and that is removed when shocking. We have shocked the 475 gal spa twice since the new water was delivered and have only used it once or twice a wekk adding 1 teaps of diclor. When I check to spa in between uses, it always seems to register the same 3 - 5 ppm.

Is the small amount of chlorine on skin normal? We didn't have that when using dichlor with EZ spa.
Tony

[tinybubbles]

Hi Tony.  1 tsp of dichlor in a 475 gallon spa doesn't seem like it would be enough to give you 3-5 ppm fc the next day.  You must have a very low sanitizer demand.  Are you testing for free chlorine and combined chlorine?  What testing method are you using?  How much mps are you adding when shocking?  I can tell you that from my experience, it isn't normal to have a chlorine smell on your skin.  It seems strange that 1 tsp. of dichlor in a 475 gallon spa once or twice a week would maintain a 3-5 ppm fc reading in between uses.  Any chance you are using an oto test kit and registering total chlorine?   It certainly shouldn't be enough chlorine to make your skin smell.  One possibility is that the water you use to fill your spa has alot of chloramines in it and you haven't burned those off.  

[Tonyf]

Hi TinyB;

I use a 4-1 test strip that is new. I took a sample of the water after it was filled to the dealer and they checked it and the combined chlorine was .2, total .4 and free .2 and they recommended adding 2 oz of dichlor. We haven't used the spa in four days at which time I added a teaspoon of dichlor after use. I just tested it and it is at 3ppm with alk at 90, ph at 7.4 and hardness all great. When I have shocked it the past two times, I used 1 1/2 oz MPS and 1 oz dichlor.

The initial reading of .2ppm of combined chlorine was high, but my thoughts are that after having shocked it once a week for the last two weeks would have burned off the chlorimines. As I recall from other posts, it is the chlorimines that give the chlorine odor.
Any suggestions? Should I use more shock? My wife and I use the spa about 15 minutes twice a week lately due to busy schedules, so the demand may not be that great.
Tony

[tinybubbles]

I would use more MPS.  The recommended shock rate is 1-2 ounces per 250 gallons. One great thing about mps is that you won't overdose with it.  Even at high levels you can use your spa.  Any extra will hang out in your water, ready to oxidize waste.  As far as the 1 oz of chlorine you are using when you shock, you don't need to combine the two to shock.  You need to use more of one or the other.  If you want to shock with dichlor instead of mps, you would need to reach 20 ppm fc to reach breakpoint with your .2ppm cc.  As I am typing this I just remembered something worth mentioning.  The mps will register as total chlorine on your test strips.  You are correct that chloramines are responsible for odor, not free chlorine, unless your free chlorine levels are very high.  Remember to leave your cover open after shocking.  

[Tonyf]

The MPS contained says to use 3 tablespoons for 500 gallons which is what the dealer indicated. It does make sense though that I am not getting rid of all the chlorimines which is causing the smell.

I thought it was necessary to use both dichlor and MPS when shocking, is that not correct? Also, what is chlorine lock?
Tony

[Cyn]

What kind of MPS are you using?  Mine suggests a higher dosage as well.  When shocking you can either use the MPS or dichlor, but you don't need to use both.  Usually, when dosing with dichlor after usage you will find that it pretty well dissipates by the next day.  You are saying you add the dichlor after use and then find several days later that you get a 3-5 ppm reading of FC?  What is your TC?  I am not sure what chlorine lock is, but someone will come forward with that info!!  MPS will register as CC until it is completely used up, I believe.  We used EZ Spa on our intial fill as well and I got so fed up with not being able to actually measure the FC and not getting any help from our dealer or even the sales rep for EZ Spa.  I switched to the Vermonter Method so heavily recommended on this forum and have had great luck!!  So there is light at the end of the tunnel!

[Tonyf]

The MPS I am using is called SPA Shock Out and it appears to be a private label of the dealer made by Haviland Consumer Products and it does state not to exceed the recommended dosage of  3 tablespoons per 500 gallons. My test strips only measure FC. When I shock the spa, I add the MPS and also add 1 ounce of DiChlor at the same time. Maybe I should not be using both at the same time? When I was using EZ Spa, the dealer had me use both the EZ Spa and Dichlor when shocking which is why I continued using dichlor with the MPS.

You are correct in the fact that I was trying the Vermonter style by adding 1 teaspoon after each use to begin with and I get a reading of 3 - 5 ppm several days later with no spa use inbetween.  The water is crystal clear with the only problem of the chlorine smell. What am I doing wrong?
Tony

[solo]

I have had my spa for 4 months.  So far, no water issues other then getting the water chemnistry to stabilize upon first filling. I use:

1.  A Nature 2 ion stick in the filter
2.  Ozone
3.  Dichlor

That combination works very well.  Again, no issues for me.  No need for MPS or anything else.  Also, why not sanitize the spa after you and your wife get out rather than before?  That would prevent you from being exposed to so much chlorine and probably keep the chlroine smell off your skin.  

Good luck!

[tinybubbles]

I don't think you are doing anything wrong.  You just need to tweak your routine a bit.  To answer your question about chlorine lock...usually people are referring to water with really high levels of cya(stabilizer) which binds with fc lowering it's effectiveness.  There is great debate over wether this is an issue or not.  Most of us here use the vermonter method and none of us have had problems with cya.  I don't think that "chlorine lock" is the issue with your spa.  Your question about using both mps and dichlor to shock.....there is no point in doing that.  You need to use the right amount of one or the other.  Using almost enough mps and almost enough dichlor will not do the trick.  What brand test strips are you using?  Read your bottle of mps and see if mps is the only ingredient or if it has ph buffers, etc. in it.  Perhaps the dose they recommend is assuming that you are using it with the ez spa product.  Duopont's website suggests 1-2 oz per 250 gallons.  If you are familiar with vermonter's method you know that readings are more important than the amount you add.  You have to add enough product to burn off the cc.  The only other thing I can suggest is using a spa fragrance product when you soak.  It would mask the slight chlorine odor you are experiencing.

[Cyn]

I would suggest a Taylor Kit to test all your chlorine levels.  You need to know your FC, CC and TC to get to the bottom of why you have such a high FC days after a normal dichlor dosage.  Not sure about your MPS brand and why it is so different in dose requirement from what most of us are using.  Checking and correcting your pH, alk and then FC on fill up; dosing your tub after use with a teaspoon of dichlor (or what you decide is needed through checking your FC levels after about 20 minutes to 30 minutes of dosing) so that you get a 3-5ppm FC reading at the 20 to 30 minute mark should set you on the right track.  If you aren't dosing or using the tub for a couple of days, you most certainly should have a zero FC reading.  Most users just put the maintenance dichlor dose in AFTER using the tub if they are tubbing several times a week.  If you go more than a couple of days without using the tub and therefore without adding dichlor, you might want to use the maintenance dose just to bring the FC level back up to 3-5ppm (you don't want to go too long without any sanitizer in the water).  Every week you should check and adjust your pH and TA and get a good reading of your CC.  Higher than .2 on the CC reading means it is shock time.  MPS or the shock dosage of dichlor mentioned earlier (enough to reach 10 times the amount of CC you have in your water.  Once again, adding the dichlor and checking the FC at 20 minutes will tell you how much FC you have in the water and you add more if needed to get to that point), but you don't need to use both MPS and dichlor to shock.  You mentioned your strips only read FC...how did you know you had a CC reading of .2?

[Tonyf]

The dealer tested a water smaple and they gave me the .2ppm reading. I will try a higher does of MPS and just use MPS to shockwithout dichlor and see how that goes.
Tony

[sonofsail]

I agree you should get a good test kit.  Here is the  one recommended by the experts on this forum. http://www.taylortechnologies.com/products_kitinfo.asp?KitID=2227
I got one and it is well worth the cost.  Not only does it test everything you need to know, it also has a great reference manual that all hot tub users should read.  
I have had a tub since Sept. 07.  I got great advice here.  I use the Vermonter method and it works very well.  I shock with MPS once a week for a few weeks then with dichor once a month instead of the MPS.  This way I get a good sanitizing from the dichlor.  I also have an N-2 mineral cartridge and ozonator that keep the water very clear.  Good luck.  

[windsurfdog]

I agree you should get a good test kit.  Here is the  one recommended by the experts on this forum. http://www.taylortechnologies.com/products_kitinfo.asp?KitID=2227
I got one and it is well worth the cost.  Not only does it test everything you need to know, it also has a great reference manual that all hot tub users should read.  

If there were only one source of water management information, the Taylor book would be it, IMHO.  Should be required reading for any hot tub/pool owner... 8-)