Getting the chemistry under control...

[aseigler]

I finally got a real test kit last week, and I am starting to get things under control. Had some algae to clear up, kept FC up around 27 for a few days until I passed the OCLT which was overnight last Thursday night. Thursday night FC was 27, Friday morning before dawn FC was 26.5. Friday night it was 22.5, Saturday night 19.5, Sunday night 16, Monday night 13, and tonight, Tuesday night, 10.

Ran a full set of tests:

• FC = 10
  CC = 0.5
  TA = 230
  CH = 360
  PH = 8.0
  CYA = 60

Looks like I am losing right at 3ppm per day. Does that seem reasonable? Based on that I need to be dumping in a bit over a half a gallon of liquid chlorine per day. Does it have to be every single day? Liquid chlorine here comes in 2.5 gallon jugs at 10.5% for about $4 a jug. That works out to a little over 1 jug a week during the time when the water is warm enough to support algae growth. Is there an advantage to having the FC level fluctuate daily between 7 and 10 versus just dumping in a full jug every 5 days and letting the FC jump up to the low 20's and then drift back down?

My PH is high. Is this a false reading because the FC is still high? I ran an acid demand test with the old PH kit I had and it seems like I need about another gallon of acid to drop the PH down to 7.5. The colors in the PH and borate tests are really frustrating, they all look way too similar. Why can't all the tests be super high contrast like the FC test or the TA test?

Thanks yall, it is so much better now that the green is gone for good!

 

[jblizzle]

That seems remarkable actually. Usually you lose a % of the FC, which means you would lose more ppm at higher levels. I would not have been surprised with a 40% loss each day. This is why we recommend adding each day as you should end up losing less to the sun than if you try to only add weekly.

You pH is probably pretty close since your FC is right at 10ppm.

 

[aseigler]

Over 22ppm I was losing way more than below 22ppm. It's been raining more the past few days, which has left fewer hours of sunlight. The pool is screened, I think that might make a little bit of difference in how much sunlight gets in, but I'm not sure if it is measurable. I've been very careful in the FC testing. I'm pretty sure I'm going to have to get another bottle of the solution before the summer is over.

 

[Richard320]

How green was it? We've had posts here where people struggle with high demand for weeks despite perfect chemistry and sparkling water, and they discover some algae hiding behind the light or inside the steps or under the ladder rungs. It might be worth investigating.

 

[jblizzle]

Clouds and a screen certainly will change the FC loss rate ... that explains it.

 

[aseigler]

It wasn't too bad, it was crystal clear before a 5 day, 12 inch plus marathon storm like we often get in May to start our rainy season. It took one week to get it back to crystal clear from the time I started testing and maintaining proper shock level. Are you saying that 3ppm per day sounds excessive in this scenario?