First appearance of Algae

[Watermom]

You really need to get your own kit so you won't have to rely on the pool store. And, with high CYA, you're going to have to run high chlorine levels as Janet mentioned. You need a kit that can test as high as you're going to need and the K-2006 kit will do that. If you haven't already done so, please read the Best Guess Chlorine Chart in Janet's signature above. With a high CYA and chlorine at only 3ppm, you are going to have algae problems. (It is actually very likely that you really have CYA over 100 since that test can't differentiate values past that.)

[aylad]

To determine whether or not you have an algae issue, the easiest way is to test the chlorine at night after sundown and then again in the morning before the sun hits the pool and see if you've lost any chlorine in that time. If you've lost more than 1 ppm, then you have something eating up your chlorine and the pool needs to be shocked. If not, then you know that's not the issue. However, this requires being able to do your own testing. In your case, if you have any doubt at all, I would shock the pool anyway just because your chlorine levels are way too low for your CYA level.After that, you're going to need to keep your chlorine at a minimum of 8 ppm to make sure the algae stays away.

I don't see any problem with using the lithium chlorine that you have--I've never used it, but I know that it's one of the most expensive forms of chlorine that you can use--I certainly wouldn't go buy any more of it, but I don't think it would be a problem to use up what you already have. After that I would switch to bleach.

Janet

[pgeifert]

Janet,

I will shock the pool with the Lithochlor and get a test kit. I have been using bleach up to now and had great results. I guess i need to get the level up to 25ppm and then maintain it at 8.

Thanks,

Paul

[aylad]

Sounds like a plan.

Maintaining your chlorine levels "that high" will not be irritating to swimmers. A pool with CYA of 100 and a chlorine of 8 ppm is no more irritating that a CYA of 30 with chlorine of 3. The CYA makes the chlorine less aggressive (hence the need to up the chlorine levels when the CYA levels go up). You can even swim at shock level if you want...it might irritate the eyes a little, and I certainly wouldn't wear new, or Lycra, suits, but it wouldn't hurt you. The elastic in the newer fashion suits doesn't hold up well to high chlorine, though, so wear an old suit.

As far as your CYA level goes, you can drain/refill part of the water if you want to, to lower the CYA levels--it would allow you to run lower chlorine levels. However, I run my pool at 90-100 CYA on purpose because I lose substantially less chlorine to the sun that way than I do at lower levels. It also allows me to dose the pool every 2 or 3 days, instead of everyday and still keep my chlorine where it needs to be. As long as you keep it in the ranges per the chart, for me, the higher CYA pool is easier to run. The only downside is if you have an algae bloom--it takes an immense amount of chlorine to clear up, but I find it easier to keep the algae blooms away with the slower-disappearing chlorine from the higher CYA levels.

Your choice.

Janet

[PoolDoc]

membership upgraded. -ben

[pgeifert]

Dear Watermom,

I do know I need my own test kit and will get one immediately. I am not working currently and am trying to avoid any expense possible. I have read the Best Guess Chlorine Chart and am wondering if maintaining chlorine that high will be irritating to swimmers? Do you think I should dump about 8,000 gallons of water to get the CYA level down? That is what the pool store suggested.

Thanks,

Paul