Running FC above Pool Math recomended numbers

[miwitte]

So I have been running the TFP method for a year now, and have some observations and questions. I have always ran the pool at the recommended dosage of 8PPM in the AM, let it fall during day and then added at night. I got a Stenner a few months back and its works perfect, a 30 min run yields 1 PPM in my pool so easy to dial it in. I was doing the same thing running it at 8 PPM (50 CYA) in the morning, my pool loses 3-4 PPM per day and then run it at night. I had a algae issue due to a fitting failure on my injector and had to SLAM it and noticed after the slam how great the pool looked. I saw some folks here inject all day to maintain the upper end I was wondering about running higher say 2X the recommended in Pool Math. If you look at this chart of HOCL VS CYA http://troublefreepool.com/~richardfalk/pool/HOCl.htm , you can see that CYA drastically reduces the amount of algae killing chlorine (HOCL). For me running it at 4-8PPM FC and 50 CYA I am in the .03 to .08 PPM of CL2(actual chlorine killing part) Since Dept of health allows 3PPM of FC in our drinking water at CYA of 0 is it safe to run even higher levels of FC than what pool math recommends?

I know one reason is because we cannot reliably measure PH when FC gets above 10 but is there any other reason to not run at say 15 and then let it come down once a week to check PH? The reason I ask is I wasn't home all last week and had someone look after and they didn't do the drop thing right, when I got home the pool was sitting at 15 PPM when it thought it would have been 8 or so. In any case the pool looks fantastic I haven't seen it sparkle like that in quite some time (Except after a SLAM)

As always curious about things. The TFP method is great only failed me when I had the Stenner issue other than that 1 year of Trouble free pool but always looking to improve my water quality. It looks so good now just had to ask this question.

 

[Pool Amateur]

No expert here but have and still am considering something similar. I may very well be wrong but I thought I read a chemgeek's post saying drinking water was down in the .5 range, but also read people testing tap water to be 1. I also think I remember a post from chemgeek where a person was running higher FC with solar cover and he explained how it deteriorates solar cover much faster and other problems. I have searched for these threads but haven't found them yet. Also I read in a thread where swampwoman and a few others who have trouble with algae, keep their FC level a few points higher. This is my second year of TFP method, works great, except when I use solar cover, and have ended up using 7 ppm as my target (CYA=40). My pool has stayed clear but 2x have had algae grow in skimmer. Wiped away algae took pool up to slam and passed OCLT 1st night. So I would also like to here some opinions on this and how much over recommended targets are ok. However if I had a Stenner pump I would set it to run throughout the day adding small amounts so I would always be very close to target.

 

[duraleigh]

but is there any other reason to not run at say 15

You will lose a lot more chlorine. You typically lose a percentage of your FC not a set ppm.

So, if you lost 3 ppm daily at a starting FC of 6 ppm, you would lose closer to 5-6 ppm if you started at 12 ppm.

 

[pooldv]

Also, the PH test is not valid when FC is above 10 ppm. I am one of those who runs FC a couple ppm higher than target because we have lots of trees and varmints adding stuff to our pool and have no ended up with algae a couple of times. I keep my FC at 8-9 ppm with SWG and CYA at 80. Works great, no algae. And my pH test is still good.

 

[Saturn94]

Also, the PH test is not valid when FC is above 10 ppm. I am one of those who runs FC a couple ppm higher than target because we have lots of trees and varmints adding stuff to our pool and have no ended up with algae a couple of times. I keep my FC at 8-9 ppm with SWG and CYA at 80. Works great, no algae. And my pH test is still good.

I also keep FC a little above target; 7-8 ppm with SWCG and CYA at 80. This seems to be the sweetspot for keeping my pool clear/sparkly without wasting a lot of chlorine.

 

[miwitte]

Great point about the FC loss. So my plan is to add during day to keep at upper limit