Test results on new pool in Tucson

[PoolDoc]

Maybe I've missed it, but I haven't seen a chlorine level reading in the late PM, followed by another reading the next early AM.

Those two readings TOGETHER are what gives indication of what's happening. A chlorine reading -- with no time stamp -- followed by a chlorine dose -- with no time stamp -- followed by another reading the next day -- still with no time stamp -- is not particularly informative.

Also, you write that a gallon per day is not sustainable. At Walmart, fresh bleach is under $3/gallon in most locations. For a 120 day season, that's $360, which is much LESS than most pool owners spend on their pools during a 120 day season, when following pool store recommendations. So while I'm not advocating a gallon per day as normal, a whole lot of pool owners sustain even higher expenses.

Let me be more specific.

1. Raise your chlorine level to a tested 15 ppm or higher at 7 pm.
2. Add nothing else. Make sure your pump is on all night.
3. Test again after sunrise, but before 8 am.
4. Report BOTH results.

[Wilco]

This is the first time I have seen the timing of the pump come into play. Is it better to run it at night? - from a cl standpoint? Sorry about not time stamping posts, I thought the server was doing that. So in general, try to do the chlorine adding at dusk, retest an hour later, and then first thing in am as the routine? Going to need more of that powder soon.

[FormerBromineUser]

Wow. Lots of responses here. Told you that you would get support!

Run pump 24/7 during shock process. Before you order more powder, check other supplies, especially 0871. Amato Industries (usePoolDoc/WaterMom's amazon link in their signatures) will discount shipping the more you buy. It won't look like it as you add to cart, but will be reflected at check-out.

[Watermom]

Sorry about not time stamping posts, I thought the server was doing that.

It's not the time stamping on the posts that is important but the time you tested along with the results that we need to see. Being able to see the change from sundown to sunup is particularly telling when trying to diagnose what is going on in a pool with chlorine demand. As Ben noted in an earlier post, losing chlorine during the day could mean that your CYA is low. But, losing chlorine overnight when you take sunlight out of the equation, tells us that something is going on in your water.

Once you get past this chlorine demand issue, it is not necessary to test in the evening AND in the morning. At that point, testing just in the evening is enough. In fact, once everything gets stable and you better learn your pool's behavior, you may even be able to go to testing every other day. But, not just yet.

You do need to run the pump 24/7 right now. When you aren't fighting something in the water, the time of day that you have the pump on is not as critical. But, it is always best to test and add chemicals (especially chlorine) in the evening. The only exception to this is if your chlorine is too low during the day. In that case, you wouldn't want to wait until evening to bring it up.

[Wilco]

Ok, I have been running pump 8 am to 4 pm each day. Try to run it for an hour if I add something before retesting. I know my cya is high, but the heat and high amt of sunlight seem to take their toll on the cl levels. I was hoping the overnight loss would be minimal, but will follow your instructions for consistency and hopefully diagnose the pattern soon. Thanks again.

[FormerBromineUser]

Since you lost about 6ppm FC overnight, you have a chlorine demand that will take time, energy, and faith to get rid of.

I actually did calculate based on your post-times but that WAS a hassle and I might very well have been making incorrect assumptions. Lesson learned. However, if my assumptions were correct that you lost 6ppm from sundown to sunrise, we know that something is going on with your pool. Follow PoolDoc's recipe tonight and tomorrow morning and we will know for sure:

1. Raise your chlorine level to a tested 15 ppm or higher at 7 pm.
2. Add nothing else. Make sure your pump is on all night.
3. Test again after sunrise, but before 8 am.
4. Report BOTH results.

I would clarify that a "TESTED 15ppm..." means that you wait one hour after raising CL level in #1 above, and then perform FC and CC tests again. This is just to make sure of the exact effects of any additions. These would be the numbers we need for your morning post.

Remember to record your TIME

[Wilco]

Ok , here's the last 24 hrs. Not encouraging. Yesterday 7 am, cl at 4, I added a gallon of bleach. Retested at 4 pm, it's at 5 ppm, with 1ppm cc, added a gallon retested at 5 pm it's at 10 ppm, added another gallon, an hr later at 7 pm it's at 16 ppm. Ran pump all night. Test this am showed 6 ppm, zero cc.

[Watermom]

With a CYA of 100, your shock level would be about 25ppm. Let's see if going up to shock level will get you past this chlorine demand faster. Instead of adding bleach multiple times per day, add enough this evening to get back up to shock level. An hour later, test and record FC and CC and then within an hour of sunrise in the morning, test both again. In the morning, take it back up to shock. Just try and add enough bleach morning and evening to take it back up to 25ppm instead of trying to add bleach so many times per day.

I know this is frustrating. We see this on some pools every year. High chlorine demand that seems relentless and seems as if it will go on forever. It is usually the result of CYA biodegrading causing byproducts such as ammonia that you have to get rid of. I know it feels that you'll never get past it, but you will. Hang in there.

[FormerBromineUser]

Ok , here's the last 24 hrs. Not encouraging. Yesterday 7 am, cl at 4, I added a gallon of bleach. Retested at 4 pm, it's at 5 ppm, with 1ppm cc, added a gallon retested at 5 pm it's at 10 ppm, added another gallon, an hr later at 7 pm it's at 16 ppm. Ran pump all night. Test this am showed 6 ppm, zero cc.

Carl, in Wilco's overnight test he lost 10ppm FC. That's why WaterMom took him to shock level.

Wilco, we originally said 15 because with your CYA level, 8-15 is your maintenance range. Now that you have determined that you are losing FC overnight, we know you are fighting something unusual in your pool and need to shock it at 25.

Yes, you need to add bleach in the morning too. Your goal is to get it to 25 and keep it there as much as possible. If you can, make additions mid-day too.