How to add CYA?

[mphare]

I have a DE filter and just did a backwash and filter maintenance last weekend.
I agree to add it slowly. I'm starting with just 1 lb and will add it about a lb a week until I'm at my target (about 80 ppm or so).

Thanks!

[caustik]

A couple threads on the topic.

http://www.poolforum.com/pf2/showthread.php?p=6645


http://www.poolforum.com/pf2/showthread.php?t=5377

[waste]

Mike, Hi

I found this thread which covers adding cya. I suppose I could have linked another post with my 'method' of ascertaining how much cya to add - but it's probably easier for me to just say the when I add cya to a SWCG pool I tie it to the salt - 1 lb cya/ 100 lbs salt gets you to 30 - 40 ppm , if you're shooting for 60 - 80 ppm cya, add 1 lb/ 50 lbs salt. If you know how much salt you originally added to the pool to put you in the 2800 - 3200 range, you'll know ~ how much cya to add to get it where you want it to be. (& you'll also know how much to add when you need to raise the salt)

[chem geek]

If you put the Cyanuric Acid (CYA) in pantyhose in the skimmer basket, be sure to keep the pump running 24/7 until it all dissolves (which will take a while). CYA is about as acidic as Trichlor (pound for pound -- CYA is slightly more acidic) so if the pump isn't running and the CYA dissolves during that time, then there will be a locally high concentration of acid that will flow through your system when the pump turns on. It will be brief, but generally it is safer to either keep the pump on the whole time or to put the pantyhose in front of a return jet in the pool. Perhaps this is overkill since CYA takes so long to dissolve, but Trichlor also takes days to dissolve and we know that damage has been caused by Trichlor in the skimmer basket unless the pump is always running.

Pat's option (the first link caustik put in above) of putting the pantyhose over a return jet makes the dissolving go faster (24 hours) and is safer with regards to the acidity.

There are other options for adding CYA to the pool. There is a quick-dissolving and fairly pH neutral formulation of a CYA salt called "Instant Pool Water Conditioner" made by "Natural Chemistry" and may be seen at this link. I've never used it, but I've been in communication with the chemist who developed it so it's certainly an alternative (it's a sodium salt of CYA in a slurry). Another alternative is to use Dichlor since that is also quick-dissolving. Of course, that also increases FC, but chlorine is something you need to add every day anyway so doing a "shock" with Dichlor is one way to add a lot of CYA relatively quickly. I haven't checked comparative prices for these options.

Richard

[Poconos]

Since I use trichlor pucks when I need to add CYA, and also get the chlorine, I have smashed up pucks with a small hand sledge hammer They pulverizes easily. Take the powder and dump it in the skimmer and the sand filter traps it and it dissolves very quickly. A few hours. You may be able to dissolve it in a bucket of warm water and do it faster yet. With a DE filter I'd try the bucket to prevent spots of high acid concentration from damaging the filter grids. Also, when you pulverize the puck place it between sheets of newspaper or plastic or something and clean off the hammer right away if any powder gets on it, or it will rust. Obviously wear protective gloves and eye protection. To repeat, I do this with my sand filter and have not heard of anyone trying it with a DE filter.
Al

[eljefe281]

I would like to tip my cap to PatL34. His method of adding CYA is outstanding.

From one chemical engineer to another, I thank you.

[jagwire22]

Will large amounts of CYA granules destroy your liner. I made the mistake of dumping CYA in through my skimmer before reading these great posts, I now have lots of granules on the bottom of my pool.

Thanks for your input!!

[waterbear]

There are other options for adding CYA to the pool. There is a quick-dissolving and fairly pH neutral formulation of a CYA salt called "Instant Pool Water Conditioner" made by "Natural Chemistry" and may be seen at this link. I've never used it, but I've been in communication with the chemist who developed it so it's certainly an alternative (it's a sodium salt of CYA in a slurry). Another alternative is to use Dichlor since that is also quick-dissolving. Of course, that also increases FC, but chlorine is something you need to add every day anyway so doing a "shock" with Dichlor is one way to add a lot of CYA relatively quickly. I haven't checked comparative prices for these options.

Richard

Richard, Did the chemist tell you why the product is not approved for use in California? (Then again California also does not allow borates in swimming pools so maybe they just are a bit too strict out there!)

Edit: Don't get me wrong. NaturalChemistry makes some excellent products! Their enzyme based products work very well. I have found that their EDTA based metal remover does not prevent stains from returning in a fiberglass pool as well as phosphinic acid based products such as Jack's Magic or Proteam's Metal Magic. Not trying to hijack the thread. Just want more info on the NaturalChemistyr stabliizer!

[nater]

Jagwire22,
You can vacuum the CYA to the filter (not to waste). I would not just let it sit there if you have vinyl. Better safe than sorry.

I tried the skimmer net trick, but it was not a fine enough mesh so about 30% of it wound up on the bottom of my pool. It's the first time I've had to manually vacuum in months!

[chem geek]

Richard, Did the chemist tell you why the product is not approved for use in California? (Then again California also does not allow borates in swimming pools so maybe they just are a bit too strict out there!)

Edit: Don't get me wrong. NaturalChemistry makes some excellent products! Their enzyme based products work very well. I have found that their EDTA based metal remover does not prevent stains from returning in a fiberglass pool as well as phosphinic acid based products such as Jack's Magic or Proteam's Metal Magic. Not trying to hijack the thread. Just want more info on the NaturalChemistyr stabliizer!

I've E-mailed Dr. Lowry and will let you know his response. As for Borates, I don't think they are actually banned from being used in swimming pools. My understanding is that California sets a low level of toxicity for what is considered to be a "hazardous waste" so the borates (which can form boric acid) have to have special labeling and handling instructions, plus maybe fees or something like that. This discourages manufacturers from selling the product in California (think "skull and crossbones" on the product label!). However, I don't recall any such warnings on the 20 Mule Team Borax product which IS sold in California. I don't think it's actually illegal to use it in a pool, specifically. See this MSDS for more info. This link raises concerns for using Boric Acid in broadcast applications with constant exposure. This link that I have referred to in other posts gives details about Boric Acid toxicity levels. The level in pools is way below any problem amount (for skin exposure) and some boron may be necessary as a nutrient and is found in food. I can't seem to find the post, but I did write that it would be best if borates were not used in a pool where a dog drank from it every day -- it could just get over the minimal level where minor symptoms would start, but is still far from toxic levels. The 30-50 ppm Borates were about 2-3 times this minimal problem level as the equivalent for chlorine in the water.

Richard