how often do you add bleach?

I have a 30,000 gallon concrete pool.
Cya = 100
FC = 8
Alkalinity = 80
Ph = 7.4

I am changing over from using trichlor pucks to just using 6% liquid bleach. I am in Hawaii so it is in the 80's almost every day and the pool water is warm. Should I add the bleach every evening, every second day, or what do most of you do during the summer months? I started out using about 1 gallon of bleach every second day, but I am having a bit of yellow algae on the walls even though I am keeping chlorine level at 8. Also, my test kit only tests chlorine up to 3, so I am filling the tester half with regular water and doubling the results, but that only gives me a measurement up to 6 and if it is a little darker yellow I am guessing it is around 8. How can I get a more accurate measurement?

Thanks... Vivian

Here's the chart that suggests chlorine levels. http://www.poolforum.com/pf2/showthread.php?t=365

Hi Vivian,

Good idea to change off the pucks - your CYA is high enough already. With that high CYA, you need to keep 8-15 FC. Less than 8 and your algae is very happy!:D

If I understand your testing method correctly, you're probably overestimating your FC, meaning you're probably not at 8 after all. When you say "regular" water, I'm a s suming you mean tap water. If your tap water has any chlorine in it, then you're testing the chlorine from your pool -plus- the chlorine in the tap water which will lead you to overestimate the chlorine in your pool. Use distilled water instead.

With algae an issue and needing to consistently test for higher levels of chlorine, you really do need a better testing kit that can handle higher FC levels. Of course, the PoolSolutions kit will do that but I'm unsure if you can get one in a timely manner, if at all anymore this year. I've heard that there's a Taylor kit that's good but I've not had experience with it. While the Wal-Mart 6-way test kit tests almost everything you need, it only tests chlorine to 5 without dilution, and it's total chlorine, not free chlorine.

Also, because you have a concrete pool, you should run a calcium test.

Hi again,

Missed a couple of your questions. In North Texas this summer, we've been above 100 degrees for over 50 days :eek: and have just now come down into the 80s.

Bleach added in the evening lets the chlorine go to work without being broken down by UV rays.

Instead of adding chemicals on a regular schedule, I test on a regular schedule (initially I tested 2x/day, now once a day) and add whatever is necessary, whenever it's necessary. I'd test even more if I were trying to kill off algae.

Vivian,
you could further dilute your pool water with distilled water, 2 or 3 parts distilled to one part pool, and then multiply the results by 3 or 4. This will give you up to 12. You lose accuracy with these diluting methods, but they are certainly more accurate than "Dark yellow"!! :D

This is the best thread I've seen on here in regards to how much chlorine usage is "normal". Seems to be about 2-3 ppm per day.

http://www.poolforum.com/pf2/showthread.php?t=4094

I have a SWCG so it gets added every night while I sleep ;)

You need to get a test kit that uses the FAS-DPD method to determine your Chlorine level accurately including high levels. Ben's Kit is what you need but if you can't wait here's a link: http://www.taylortechnologies.com/ They will send it out same day so you could have the kit as fast as the delivery can get it to Hawaii. There are several kits -- The K-1515-A only does FAS-DPD.

You need to add Chlorine as often as your test dictates. To get rid of your algae your Cl needs to go to shock level (25 ppm) and keep it there even if you have to add 5 times a day. Of course you need to brush vacuum and brush some more. After holding the CL up there you can let the level drop to between 8 & 15 ppm. DO NOT let it go below the 8 ppm.

I can't stress the importance of an accurate method to determine your chlorine level. Your safety and sanity depends on keeping the CL level where it belongs.