When would you start floating trichlor to raise CYA for season?

[QingGuy]

When would you start raising your CYA for the swim season? Here in Vegas I we'll start swimming beginning of April (today is Feb. 21). I'd like to raise it using trichlor pucks since I have a bucket of them sitting in my garage. When would you start floating them to get to 70 CYA (currently at 45) by April?

It's been in the mid 70's here and I'm starting to use more bleach to maintain a FC levelof 4.

Is this the right strategy?

FC 4
CC 0
pH 7.7
TA 90
CH 350
CYA 45

 

[Texas Splash]

That certainly makes sense to use them a bit. The trichlor tabs will increase CYA while also assisting with keeping pH down a bit. As for the rate of usage, I would recommend using the Poolmath calculator (near the bottom) and see "Effects of adding chemicals". There you can enter the parameters required to get a realistic CYA goal which should give you a good timeline of when to start using them. I would expect May - Sep to be your peak sunshine & heat months requiring the most CYA protection. If you chose to increase early, just make sure you maintain the correct FC to support that CYA as noted on the Pool School - Chlorine / CYA Chart. Still, watch it closely. As we all know, it's easy to put CYA in the water, but no way to get it out other than water exchange.

 

[tim5055]

Right now you are running a manually chlorinated pool, so for a CYA of 50 you should be targeting 6 so it never goes below 4.

There is no "45" on a Taylor CYA test, all yo can really say is it's above 40 but below 50. The scale on the tube in non-linear, so have way between the two is not 45. But, that's splitting hairs that probably don't need to be split.

If we say you are at 45 you will need 20 pucks to get from there to 70. I would go ahead and start now. Your water is warm enough to support rapid growth of algae so lets keep the FC up where it needs to be.

I would say use up about 15 pucks (that should add 18 or so ppm CYA) and stop long enough to get a good CYA level. It's always easy to add more CYA, hard to get rid of it.


*****On Edit*****

Looks like Pat & I were typing at the same time. I stole the thunder and did the Pool Math for you.

 

[Texas Splash]

Oh, and if your CYA is 45 (round-up to 50), you really should have your FC at 6 (target). Might want to bump that up and watch it closely as the sun gets more vertical on us.

 

[JoyfulNoise]

In your pool it will take five (5), 8-oz trichlor pucks to raise your FC by ten and add 6ppm CYA. It will also lower you pH and consume some TA (but your fill water may be able to compensate for that).

So add five pick to a floater and see how long it takes for them to dissolve. Then you can see how much time it will take to get to your target.

Just be sure to monitor pH and TA regularly to be careful.


Sent from my iPhone using Tapatalk,16k gal SWG pool (All Pentair), QuadDE100 Filter, Taylor K-2006

 

[QingGuy]

Thanks for all the replies, not the best on chemicals so the explanation and direction to the results of adding section of pool math help (I always forget about that).

Speaking of not being the best on chemicals, unless I'm reading this incorrectly (which I very well could be) Chlorine/CYA Chart calls for my SW Pool with a CYA level of below 60 to be at FC 4. Am I reading this incorrectly?

I think I'll follow JoyfulNoise's suggestion and float 5 pucks today. I'm not worried about pH as I'm curretly going through about 45 oz of acid a week to keep my pH at target. I will keep an eye on TA.

Thanks again for all the responses and input, I greatly appreciate it.

 

[tim5055]

Speaking of not being the best on chemicals, unless I'm reading this incorrectly (which I very well could be) Chlorine/CYA Chart calls for my SW Pool with a CYA level of below 60 to be at FC 4. Am I reading this incorrectly?

It depends, are you reading the top part of the chart (Non -SWG Pools) or the bottom (SWG Pools). Pool School - Chlorine / CYA Chart

Right now you have a manually chlorinated pool (non-SWG) so you should be using the top part. You listed your CYA as 45, so round that up to 50. Target 6 FC so that it never goes below the minimum of 4 FC.

 

[ewkearns]

As for when, I generally try to plan for balanced water and appropriate sanitizer, just as the water gets to 60 degrees....

 

[QingGuy]

It depends, are you reading the top part of the chart (Non -SWG Pools) or the bottom (SWG Pools). Pool School - Chlorine / CYA Chart

Right now you have a manually chlorinated pool (non-SWG) so you should be using the top part. You listed your CYA as 45, so round that up to 50. Target 6 FC so that it never goes below the minimum of 4 FC.

As I said, not too good on the chems. Dang, I've been running my pool all winter at 4. Thank god I haven't had any issues. I'll bump up to 6 with some bleach today and float the pucks and see if the pucks can maintain it.

Water temp is currently at 48 so as soon as I hit 60 on a consistent basis I'm going to re-install my SWG and turn her on.

 

[tim5055]

With water that cold you are fairly safe as algae reproduces very slowly at those temperatures.