Do any folks run hot tubs without CYA or less than 30ppm? How important is CYA in a hot tub?

[duganderson]

I've heard that some states do NOT allow indoor hot tubs to have any CYA. Curious why that is?

Also, I've heard folks saying a CYA of 30 makes the chlorine more gentle on ski, swimsuits, etc.? I'd love to hear from folks with CYA of 0 or lower than 30 about their experience with the chlorine being too harsh or not on skin, suits, etc.

I know CYA reduces that effectiveness of Chlorine so I'm curious how important it really is????

 

[Texas Splash]

CYA is necessary. Perhaps not so much to protect FC from the sun, but mostly to buffer the chlorine's potency from skin and surfaces. Free chlorine with no CYA is extremely strong. I can't speak for the comment about state restrictions, but @Donldson might be able to.

The link below is a great resource for tub owners.

How do I use Chlorine in my Spa (or pool)?

 

[Donldson]

I can't speak for the comment about state restrictions, but @Donldson might be able to.

I can't speak for any individual governing body, but essentially it comes from the understanding that CYA protects chlorine from sunlight but reduces it's effectiveness. If you stop there then the decision to ban it from indoor use makes sense. However, if you go further like TFP did then you see that blunting chlorine can be beneficial and allow a wider FC range that remains comfortable yet sanitary.

 

[duganderson]

Thanks for your thoughts! After re-reading the article that Texas splash suggested (I read it initially a while ago), I found this good discussion too.......

CYA in Spas and Indoor Pools

This thread is a response to posts in the thread Trichlor Tablet in Skimmer of Hot Tub and PMs from the now banned user HotTubTips. This user was banned due to an escalation that ventured into what came close to legal threats or warnings. I will address the issues technically in this thread...

www.troublefreepool.com

 

[Plettschner]

Rather than start a new thread, I'll add (on topic) to this one...

For hot tub start up using chlorine, is there any reason I can't add a sock in the filter with a bit over an ounce of CYA to get me into the 30-40 range (310gal) and then go straight to liquid chlorine, rather than going out to find and buy dichlor?

 

[CuckooChris]

Nope, I'm actually gonna do that next refill. Dichlor is going into the pool.

 

[jseyfert3]

Rather than start a new thread, I'll add (on topic) to this one...

For hot tub start up using chlorine, is there any reason I can't add a sock in the filter with a bit over an ounce of CYA to get me into the 30-40 range (310gal) and then go straight to liquid chlorine, rather than going out to find and buy dichlor?

There’s no reason you can’t add CYA instead of dichlor. The dichlor then bleach method came about presumably because people already had and used dichlor on their spas, and didn’t have CYA laying around.

I do just this. I personally skip the sock. If adding CYA to a heated tub, I just pour it all right next to the filters, kick on both pumps on high, and the CYA is dissolved within one or two pump cycles.