General Balancing Questions and Combined Chlorine?

[Econdron]

I'm using a LaMotte ColorQ 2x Pro 7 tester because I seem to have issues differentiating between the different shades of colors, perhaps I'm a little color blind. Anyway, I have a couple questions about some of my results as well as some questions about CYA recommendations on TFP:

1) - My pool is roughly 22K gallons, Fiberglass w/ SWG. My FC results were 3.07 and TC was 3.29 leaving my CC at 0.22. From what I understand, I've read that to get rid of CC, you need to raise your FC to 10x the level of CC. I guess I don't understand how this makes sense, as CC has to start somewhere, so it will always start when FC is at least 10x the CC, such as in my case, correct? Is it normal to have small amounts of CC that resolve on their own? I tested the water about 3 days later and the CC levels were pretty similar. The LaMotte app with the tester keeps telling me I need to shock the water because of the CC levels, but I'm not even sure what I need to raise the FC to?

2) - Is weekly shocking recommended, or is it just recommended to shock the pool when CC levels exceed a certain limit?

3) - According to TFP, I should keep my CYA around 40-50ppm and my FC at 5-8ppm. This seems really high, I've seen warnings stating you shouldn't swim unless the FC is below 5ppm. Are those warnings just BS? I guess I'm not sure why the FC should be that high.

 

[Texas Splash]

From what I understand, I've read that to get rid of CC, you need to raise your FC to 10x the level of CC.

I've never heard of that one. We consider a CC level of 0.5 or less as zero CCs so you are fine. No need to do anything specific at this point.

Is weekly shocking recommended, or is it just recommended to shock the pool when CC levels exceed a certain limit?

Neither. We here at TFP do not door "weekly shocks" as they are basically redundant. If your water's FC-to-CYA is constantly balanced as noted on the FC/CYA Levels then no shocks are required. If you happen to get algae, then you start the SLAM Process.

Are those warnings just BS?

Yes. Those are years of "generic" guidance without regards to the true FC/CYA relationship. The FC/CYA Levels ensures a consistent 7.5% ratio strength is maintained for safety and sanitary purposes. But a pool store will never tell you that. Learn more at our Pool Care Basics page.

I'm going to tag @Jimrahbe for any additional tips on your ColorQ. Welcome!

 

[Econdron]

I've never heard of that one. We consider a CC level of 0.5 or less as zero CCs so you are fine. No need to do anything specific at this point.


Neither. We here at TFP do not door "weekly shocks" as they are basically redundant. If your water's FC-to-CYA is constantly balanced as noted on the FC/CYA Levels then no shocks are required. If you happen to get algae, then you start the SLAM Process.


Yes. Those are years of "generic" guidance without regards to the true FC/CYA relationship. The FC/CYA Levels ensures a consistent 7.5% ratio strength is maintained for safety and sanitary purposes. But a pool store will never tell you that. Learn more at our Pool Care Basics page.

I'm going to tag @Jimrahbe for any additional tips on your ColorQ. Welcome!

That's good to know! I'll keep reading up here on the forum and slowly build up my knowledge base. Here's the link I found online about the 10x rule, maybe I just misread it:

https://www.in.gov/health/files/How_To_Shock_The_Pool.pdf

 

[reggiehammond]

Also good reading: Swimming Pool Test Kits Compared

 

[Jimrahbe]

E,

I have the ColorQ Pro 7 and have found it has good points and some bad points.

FC reading is low by 1 or 2 depending on how fresh the reagents are. If my ColorQ measure an FC of 7 it will really be 9.
CC, I don't use it for CC's but it seems to work. It reads Total Chlorine, so TC- FC = CC.
pH, it reads pH better than I can guess using my eyes.
TA, works ok depending on how fresh the regents are.
CH. The color Q reads Total Calcium, and not Calcium Hardness. Depending on your local water, the reading can be off by several hundred.
CYA. I have seen a difference between one batch of pills and a new batch of pills of over 20 points. it gives you a good guess.

To your point of weekly shocking.. I have the saltwater pools. In total they have been TFP pools for over 25 years. I have never added a single bag of pool store shock. As Pat points out, if you keep your FC and CYA in the proper relationship, you will not get algae and you will never have to buy bags of shock again.

Thanks,

Jim R.

 

[IceShadow]

I've heard the "you need FC equal to 10x CC to get rid of CCs" thing before. It's not true. Even if it were, and you needed to have 10x the level of your CC in FC to get rid of CCs, then it would happen over time anyway, because the chlorine and chloramines aren't going to be 100% evenly distributed through your pool. Locally you'd have areas here and there with lower CC and higher FC, and the CC would be eliminated, increasing the areas locally with 10x FC compared to CC.

Either way, it's been proven on this forum time and again that sunlight/UV is all that's really needed to eliminate CCs (but keeping FC up in the right range is important too, because otherwise algae could be growing and more CCs could be produced).

 

[Econdron]

E,

I have the ColorQ Pro 7 and have found it has good points and some bad points.

FC reading is low by 1 or 2 depending on how fresh the reagents are. If my ColorQ measure an FC of 7 it will really be 9.
CC, I don't use it for CC's but it seems to work. It reads Total Chlorine, so TC- FC = CC.
pH, it reads pH better than I can guess using my eyes.
TA, works ok depending on how fresh the regents are.
CH. The color Q reads Total Calcium, and not Calcium Hardness. Depending on your local water, the reading can be off by several hundred.
CYA. I have seen a difference between one batch of pills and a new batch of pills of over 20 points. it gives you a good guess.

To your point of weekly shocking.. I have the saltwater pools. In total they have been TFP pools for over 25 years. I have never added a single bag of pool store shock. As Pat points out, if you keep your FC and CYA in the proper relationship, you will not get algae and you will never have to buy bags of shock again.

Thanks,

Jim R.

Thanks Jim, that's very helpful to know. What are you using to compare your results to? In other words, how do you know the FC reading is low?

 

[Jimrahbe]

E,

I use the TF-Pro -Salt. For FC it uses a Drop test called FAS/DPD. This is a very accurate test that can measure FC up to 50 ppm, in .2 ppm increments if you wish.

Here is an analogy that I often use. I use my ColorQ like a standard wrench. When I want to tighten a bolt but don't really care exactly what the exact torque value is. When I need to know for sure what the torque is. I use my TF-Pro (my Torque Wrench).

I use my ColorQ quite often when I'm doing quick tests and just trying to compare what the test results were from last week vs. this week.

When I get fresh reagents for the ColorQ (from LaMotte) I run a set of tests from both the ColoQ and my TF-Pro and compare the results. I do the same when I get new reagents for my TF-Pro.

Thanks,

Jim R.