CYA concerns

[Chad]

The Taylor book recommends a CYA of 30-50ppm. After the first month of usage my water was at 40. I tested again today, 9 weeks in, and it's at 110-120. Is this a cause for concern even if my water is still clearing up pretty easily? Your thoughts would be greatly apreciated as usual.

[Brookenstein]

I researched this about a year ago or so when my water wasn't reacting the same to my normal routine.  I took my water into Leslies and the only thing that was high was CYA.  My understanding is there really is no concern unless it is very high, and up to 100 is normal.  IME I just used up more dichlor than normal with high CYA.  You can't lower CYA without a full dump, so as long as your water is good, I wouldn't worry about it.  Also, if I remember correctly if you shock with dichlor rather than MPS you will raise the CYA faster.

[Chad]

I researched this about a year ago or so when my water wasn't reacting the same to my normal routine.  I took my water into Leslies and the only thing that was high was CYA.  My understanding is there really is no concern unless it is very high, and up to 100 is normal.  IME I just used up more dichlor than normal with high CYA.  You can't lower CYA without a full dump, so as long as your water is good, I wouldn't worry about it.  Also, if I remember correctly if you shock with dichlor rather than MPS you will raise the CYA faster.

Do you know why dichlor raises it faster than mps?
Thanks for your help Brooke.

[Chad]

No need to reply anymore to this topic. Thanks to CapMorgans links in a different thread I have a much better understanding of CYA.

[tony]

Do you know why dichlor raises it faster than mps?
Thanks for your help Brooke.

Dichlor will raise CYA levels.  MPS will not because it does not contain any.  MPS will raise TDS.  I have never been concerned with TDS.  I obsessed over CYA a couple of years ago, not any more.  I like to sanitize with dichlor and shock with MPS.  Shocking with dichlor will raise CYA quickly.

[Chad]

Dichlor will raise CYA levels.  MPS will not because it does not contain any.  MPS will raise TDS.  I have never been concerned with TDS.  I obsessed over CYA a couple of years ago, not any more.  I like to sanitize with dichlor and shock with MPS.  Shocking with dichlor will raise CYA quickly.

Thanks for the help Tony.
What do you think is more of a concern high TDS or CYA? I'm asking b/c  when I shock with dichlor I use about 1 TBP opposed to 1.5-2 oz of mps. So shocking with the mps would raise my TDS faster but at the same time keep my CYA level down....right? Or should I just not pay too much attention to either one and just dump it every 2-4 months.

[tony]

No need to reply anymore to this topic. Thanks to CapMorgans links in a different thread I have a much better understanding of CYA.

IMO, it is not worth obsessing about CYA.  I've been there and done that.  I don't test CYA levels in my spa...I do test CYA levels in my pool.  As long as you get to 2-3 ppm free chlorine after soaking, you will get a sufficient kill rate.  Pools are working with constant feeds and residuals.  Its like apples and oranges.

[Chad]

Cool we posted at the exact same time. 8-)

Thanks.

[tony]

Change water as needed, but I generally go four months.  Sometimes during the summer with dirty teens loading the thing up I have to change as soon as two months.  The kids don't use it as much in the cool/cold weather which is just fine by me.

Its still the easiest thing to do...when all goes wrong just change the water...and there is nothing like fresh water.

[hottubdan]

If you are changing water every 3 or 4 months, neither TDS or CYA should be a concern.

[windsurfdog]

If you are changing water every 3 or 4 months, neither TDS or CYA should be a concern.

I second that emotion.... 8-)