Too much Cyuranic Acid

[In Canada eh]

My man needs help -- yes, you all have probably figured that out by  now --  but now he needs more help with the hot tub chemicals.

He brought in a water sample today & was told there is too much cyuranic acid (stabilizer) in the water.  He was advised to drain out 1/3 of the water & add more fresh water.

Any ideas what could have caused this?  Maybe he's using too much dichlor after each use?

Is this water state harmful to the mechanics?

He'll likely post later with more details but I thought I'd get this topic rolling ......
? :-/

[Brookenstein]

How old is your water?  Are you having any issues with it?  Did they give you a number?

A few months back my good water suddenly turned cloudy and I couldn't register any free chlorine.  Took in a sample and they said it was high CYA.  Can't remember what the number was.  I didn't worry too much about it since it wasn't tooooo high and then changed the water out a couple weeks later.

Personally if I'm going to the trouble of emplting out 1/3 of the water, I'd just completely drain and refill.

As for the cause... I never got a straight answer.  But, I had just super chlorinated to shock the day before.  I had never tested the CYA before so I dont know what my baseline was before that and whether or not it was related.

[In Canada eh]

Water is 5 weeks old following first water change at 1 month(Chas' law). Cyuranic acid level is at 130 supposedly the level should not exceed 100. The alkalinity is alittle low and the hardness is at 250(little high), but at present but no other issues, water looks good.

  We use dichlor, 1/2 oz.(18 grams) after each use, shock with MPS once a week and then rinse the filter after 48 hours, the tub also has ozone.

  Cyuranic acid is the stablizer portion of the dichlor
ie. 62 % chlorine and 38% cyuranic acid. Does this mean that we are using to much after each use? I would imagine thatthe water should last alot longer than 5 weeks, if not it could cause some problems in the winter.  Tub is also on the small side 1150 litres( 250 imp. gals or 300 us gals.  Any help all of you could provide would be greatly welcomed.

[anne]

Sounds like a lot of chlorine. I thought a pretty good rule of thumb was 1-2 tsp after use. 1/2 oz is quite a bit more than that. I use 1 tsp per person after each use.

[In Canada eh]

I decided to drain the tub completely, Why bother lowering only 1/3 of the water level. My new question now seems to be, can a build up of cyuranic acid be prevented or somehow treated? Since all dichlor appears to have it in as a stablizer, how do you get rid of it? Wow, the pool is so much easier to stray on top of things happen alot slower. Anybody have any thoughts?

[wmccall]

According to my kit the CYA gets up above 100 about a month into a new filling every time.  Yet I still get 3-4 months before dumping. My answer, stop measuring it.  

[In Canada eh]

According to my kit the CYA gets up above 100 about a month into a new filling every time.  Yet I still get 3-4 months before dumping. My answer, stop measuring it.  

I think I like your approach, is CA nothing to be really concerned over. I was told by my dealer that a high level can cause all kinds of water problems.  Yet it dosen't seem to be a issue in your tub at all. Might have to change name back to Confused in Canada

[tony]

High CYA levels will reduce the effectiveness of chlorine causing you to have to attain a higher free chlorine reading to get the same level of sanitation.  This does not seem to be as much an issue in a spa as it does in an outdoor pool where algae can chew up chlorine.

I use only a small amount of dichlor (tsp) after use along with a Nature2 cartridge and shock with MPS.  This generally keeps my CYA levels under 80 through four months.

[In Canada eh]

Thanks to all for the responce and advise. It looks like I am using to much dichlor and will lower it in the future. We looked into N2 when we bought our tub and it is not available in Canada yet, we may order from Doc because it looks like it really works.

             Thanks again