Cyanuric Acid (CYA) Level High

[Swell-Tub]

I've had my tub since May and have changed the water once for fun to see what it would feel like. My levels have always been right on the mark and where they should be. This morning I tested and my Cyanuric Acid (CYA) is at 150ppm which according to the chart on the strip box it should be between 30-50. So what makes the CYA go high and how do I bring it back down?

Thanks,
Scott  8-)

[Water Boy]

Scott,

I assume that you must be using a stabilized chlorine as your sanitizer for the spa. The stabilizer in the Chlorine is the Cyanuric Acid. Each time you add chlorine to your spa, you are also adding CYA to it as well. After so much is added it just builds up more and more, and that is why it is reading high on your strips. There is nothing you can add to lower it, other than fresh water. So in your case, I would drain and refill. But, if the water is clear and smelling good, you should still be in good shape until your next drain and refill. High CYA on pool can cause lots of problems, so I assume if too high on a spa, it can do the same as well. Here is a blurb about CYA that I copy and pasted off of the net:

The second (and more significant problem) with a high stabilizer level is that it greatly reduces the effectiveness of the chlorine in the pool.  Remember that stabilizer works by slowing down the reaction of the chlorine in the pool.  At higher concentrations, it slows down the reaction so greatly that it significantly reduces its effectiveness.  This is seen in the fact that yellow algae becomes a lot more difficult to control and the water can become dull.  The unseen hazard is that it is also less effective against bacteria, etc, leading to concerns about how sanitized the water may be at any particular moment.  The kill time of chlorine is normally measured in milliseconds, but at high stabilizer levels, the kill time becomes seconds and minutes, and time is critical in water sanitization.

Hope this helps!

[Vinny]

Scott,

What Kimbo Slice said is basically true but I want to clarify some things up.

Pools deal with algea and spas generally don't. Bacteria can be a problem but it tends to be not a problem usually.

ALL spa owners who use dichlor will raise their CYA levels to over 300 by the end of a water's life. For every 1 PPM of dichlor you add you are adding 0.9 PPM CYA. Shock to 10 PPM with dichlor, you are adding 9 PPM CYA; if you use the tub a lot - CYA will build up quickly. As was said in a different thread, spa owners do not regularly test for CYA in their water.

First the bad news - anytime the CYA goes above about 50 PPM the ability to kill the hot tub itch bacteria becomes harder due to the buffering effect that CYA has on chlorine AND any CYA other than trace amounts make it impossible to kill cysts in the water.

The good news is though that generally speaking we aren't fighting the hot tub itch bacteria and all other bacteria is relatively easy to kill even at 300 PPM CYA.

Algea is a bugger to kill and takes enormous amounts of chlorine to kill if it gets bad. Algea may even eat CYA if it is a certain type.

If you have a concern, you can do a partial water change and remove some of the buildup thats in the water, do a complete water change and start out at 0. Most don't worry about it and I am currently using bleach as my chlorine source to see how it goes so that there is no extra CYA buildup.

[wewannahottub]

Vinny and Kimbo--Awesome stuff here.

Vin-weren't you doing an experiment with bleach and your pool??  I remember a while back you talking about bleach and CYA levels.  

I need to get a different test kit for my pool, but we have found that the common household bleach has been better for clearing up and maintaining a higher Chlorine level in the pool than just shock and tablets.  I do know I need to get test strips, and read up on this more, however, we will probably just use bromine (I used that in the past) for the hot tub.  

Just curious on how it has been going.  

[In Canada eh]

I've had my tub since May and have changed the water once for fun to see what it would feel like. My levels have always been right on the mark and where they should be. This morning I tested and my Cyanuric Acid (CYA) is at 150ppm which according to the chart on the strip box it should be between 30-50. So what makes the CYA go high and how do I bring it back down?

Thanks,
Scott  8-)

Scott,

   Before you change your water , take a sample to your dealer for testing.  Often test strips are out of date or inaccurate for levels such as CYA.  2 month old water at 150 ppm CYA seems a little high in my opinion.  Other then that little tidbit Vinny and Kimbos advise was spot on.

[Steve]

Great news for ya swell-tub! Don't bother testing for it! TDS & pH will have a far greater impact on the effiency of your chlorine than the CYA.

[Vinny]

Vinny and Kimbo--Awesome stuff here.

Vin-weren't you doing an experiment with bleach and your pool??  I remember a while back you talking about bleach and CYA levels.  

I need to get a different test kit for my pool, but we have found that the common household bleach has been better for clearing up and maintaining a higher Chlorine level in the pool than just shock and tablets.  I do know I need to get test strips, and read up on this more, however, we will probably just use bromine (I used that in the past) for the hot tub.  

Just curious on how it has been going.  

I've been using bleach for years in my pool. As I measure all the parameters, I alternate chlorine sources ... My prefered method is cal hypo but once the pool reached 350 to 400 cal reading I stop and use bleach. I use trichlor pucks for either raising the CYA level and/or for vacations. Bleach can loose effectiveness with heat and light so I keep very little in stock so that means going to the store often.

I started using bleach in the tub though and it has been going well BUT I seem to have chlorine lock and a 3 PPM chlorine dose can last a long time.

[Swell-Tub]

Thank you all.

I put the hose on the drain and will let it drain tonight and put in fresh new water tomorrow. Heck water is cheap and feels good. Since it is so hot down here it also doesn't take long to heat up the new water. The water is always crystal clear and does not itch. The only thing I have done different is add some Lavender scent. I do add chlorine after each soak and shock each Saturday. Once a month I add stain and scale remover and rotate the filters. Clean the filter coming out and I put it away to dry. This is the first time any of my numbers have gotten out of whack.

BTW wewannahottub what is going on with your tub search?

Scott  8-)

[wewannahottub]

Thanks for asking, Scott.  We have gotten so caught up in summer and summer activities, that hot tubbing has taken a back seat.  And, to boot, the Tundra we were waiting for is in, all I need to do is schedule the wet test.  I was hoping to do this early next week, but I work nights M/T/W and doubt we'll be able to. Plus, not having it means not paying for something I could easily spend 12k on, not to mention, there are things I could better spend that 12 k on.  :-/ :-/

Hey, way back, thanks for letting me know I was missed!!  

[Swell-Tub]

Plus, not having it means not paying for something I could easily spend 12k on, not to mention, there are things I could better spend that 12 k on.  :-/ :-/

Hey, way back, thanks for letting me know I was missed!!  

You know I was going to replace my old Lexus with a new one but I bought the hottub instead. So first I saved the additional money a new car was going to cost me and the 12K was worth every cent of it. The improvement at work with the pains gone, the better quality of sleep, and improvement in other areas is worth 12K. You are just going to have to take my word on it for now. Another option is start with a mid level tub and see if you use it. Down the road when your ship comes in you can go for the gusto..

Scott  8-)