Help, even bleach disappears

[bcrumb]

ok, you were right. My test shows cya at 100 now, maybe a little higher. It is cloudy now and drizzling so the sun is not out. I tested again using Kroger purified drinking water, sorry forgot to buy distilled when I went back to Kroger for more bleach. My test showed around 20 ppm chlorine and like I said 100 on the cya. I am a few inches short on water level right now so I am hoping these several days of rain predicted will refill it for me. If not when I top off I will dump a little and get the cya down to around 80 again. I noticed you did not comment on the algae I always seem to have in the liner clip around the steps. I assume this is not normal but I have had it for years. Also, a co-worker has a similar set up as mine, de filter, goldline swcg, but 40000 gallons vinyl to my 28000. He claims to run his pump and swcg only 6 hours per day. I have to run mine for 12 to 14 hours and still have no chlorine. He claims to read a constant 4 with his system and run time. Is this possible? The Hayward people told me that the t15 system would have to run at 100% 24/7 to make enough chlorine to keep a 40000 gal pool at 3ppm. He told me that mine should then have to run about 28/40(or 16.8 hours) to keep my pool at 3ppm. If this is true, it makes me want to run dual swcg systems so I can cut down on the run time. With the above readings, have I reached shock level at 20ppm? Do I need to dump some water tomorrow and do the whole thing over again with a lower cya? Thanks for all your help by the way!

[CarlD]

Ok. I'm not an expert on persistent black algae, but I can tell you that you need to get your chlorine level up even further, to 25, and keep it there for a number of days before it will stop crashing on you.

Will it get rid of the black algae? I don't know, but you need to brush it daily to have a hope.

I cannot really comment on what Hayward told your friend as it makes no sense whatsover and something must be garbled in translation. There are just too many inconsistencies. I'm no SWCG expert either but I know enough. The t-15 is their biggest cell, designed for pools up to 40K (though you usually want to go bigger than the pool). 3ppm of FC is the normal production level for just about any SWCG and should be matched with a CYA of 60. For the cell to have to run at 100% 24/7 to produce that just doesn't add up. Do you both have the same controller as well?

[bcrumb]

Ok, I have five new gallons of bleach. I will go back down and bump it up to 25 or so. These several days of rain may come in handy to keep the sun at bay and allow me to pull this off. The Hayward story came to me directly from the Hayward tech support via a phone call. The story about my friend was the fact that he runs his for six hours, and yes we both have the goldline aquarite system. He runs a Hayward cell and I am running a compupool, that is the only difference other than the size of the pools. I have run Hayward cells in the past and I have not seen any difference between the two, other than price. Maybe I need to go back to the brand name cell, who knows.

[bcrumb]

My chlorine held at the 25 mark overnight. I got in the pool, reluctantly, with a small brush and went around all the fixtures(lights, returns, skimmers, rope hooks, and steps). All of them had algae, both green and black. In some cases long strips of black or dark green stuff were brushed away. I have seen this before, but I thought it would be good to clean it off while the water is at shock levels. I also snapped the covers off the tracks around the steps and cleaned them with the brush. I added one more gallon of bleach for good measure. I am going to do some research on this forum about the black algae. I have not addressed the cya issue yet, but it is raining now and hopefully that will dilute it some. My concern is whether I have a high enough shock level and how long should I maintain it at that level. I would like to be ready for swimming by Saturday.

[CarlD]

Actually, the chlorine won't hurt you at that level, but you will want to wear old suits that you don't mind being faded. And you probably don't want it in your eyes so goggles are a good idea.
If the level holds at 25 overnight for a couple of nights, I'd say you're good to go. But with the CYA at 100, you'll need to keep the level between 8 and 15 even while swimming. If it goes down to the 60-90 range, chlorine should be kept between 5 and 10.

Algae is VERY resistant to chlorine when it's attached or embedded in the walls and crevices of the pool. Brushing it out was a VERY good thing! And you should plan to do it regularly, like weekly, to control it.

Hope this helps.

[bcrumb]

Took a sample to Leslie's this afternoon. CYA read 90. This was after I drained about six inches of water yesterday and refilled. My chlorine was down to the 16 to twenty range also. This was with my test using the dilution method. Actually I ran it with a 1 to 5 ratio and it appeared to read about 4. Not very accurate but that is as close as I can get. I guess I am going to let the chlorine slowly decrease now and see where I stand. My concern is that the SWCG will not be able to keep the chlorine in the 5 to 10 range as you recommended. If that is the case, I guess I will continue to supplement, with cal hypo this time, until I can drain more water and refill to get the cya down further. Thanks, Carl, for all your help. I should have known better. I sort of blame Leslies for the incident because their guy acted like I was crazy to use bleach several days ago. He said since it was only 8.25 percent bleach that it was 91.75 percent something else and that was bad for the pool. That caused me to decide I would use some shock with the bleach. Also the heaviness and difficulties transporting the bleach added to this flawed response. As much as I have read on this forum, I really should have known better. Thanks again!

[CarlD]

Oh, wow!

Here's how I can help:
1) When your water is clear, you generally aim an SWCG to run at 5% of the CYA level--because it's a constant flow of Chlorine without ups and downs. Since most SWCGs request you keep your CYA in the 60 to 80 range, you'd keep your FC (that's Free Chlorine) in the 3-4 range. With your CYA at 90, that means you should keep it at least at 4.5--you've cleared up all the rest of the problems so you are going into maintenance mode--normal, daily care.

2) When you do NOT have an SWCG, the "Best Guess Table" is our/your guide, ie, the range I gave you. And, if you have an algae bloom, you do NOT want to use "Boost" mode from the SWCG as you will shorten your cell's life drastically. Best to use bleach or liquid chlorine. Safer, cheaper, extends the life of your cell.

3) You can find the "Best Guess" table at our sister site, PoolSolutions.com. You don't need to join, but I suggest you read EVERYTHING you can find there. It's an education in itself.

4) The Leslies guy is full of it. Bleach is made from brine so the OTHER 91.75% of it (assuming you are using regular bleach) is...SALT WATER! Yeah, that's right. And if you use nothing but bleach for 10 years in your pool you STILL won't have enough salt to run an SWCG. People without SWCGs add 50# bags of salt frequently because it makes the water feel softer. There's not nearly as much salt in bleach or liquid chlorine. Did he also try to "Pool Store" you and sell you "Phosphate removal" and calcium? If you know what you are doing, IMHO, they have some of the best supplies of any chain. If you don't, the salesmen/women may WELL try to sell you garbage--I've heard the "other stuff" argument from their people before. Buyer Beware!

5) Liquid Chlorine (LC), sometime sold in gallon jugs as "Liquid Shock" is nothing more than strong bleach, nominally 12.5%. I buy it in 5 gallon carboys, for $20/gallon. My deposit of $6 on each carboy(I have 3) was so many years ago it doesn't matter. I have a couple of screw on spigots, which are like an old-fashioned beer barrel tap, and I refill old bleach bottles and reuse and reuse them. Since bleach is has gone from 6% to 8.25%, the calculation is: If a gallon of LC is less than 50% higher than a gallon of 8.25%, the LC is cheaper to use. Otherwise, the bleach is cheaper. When 6% was the "Ultra Bleach", the ratio was double--LC could be up to 2x the cost of bleach to be cheaper.

6) If you use Cal-Hypo, track your Calcium Hardness. When it gets to 400ppm, you should stop using the Cal-hypo. When it hits 500ppm, I would say you MUST stop using it or risk your water going milky and getting scale on metal parts. Personally, I rarely use the stuff and only use Tri-Chlor in the spring or when I refilled so I could boost my CYA at the same time as my chlorine. But I also watch pH as Tri-Chlor is VERY acidic.

7) While you can ALWAYS use bleach or LC, Cal-Hypo, Tri-chlor and Di-chlor all add stuff you have to watch. Used correctly, they are beneficial. Used incorrectly, they can cause problems. Test, test, test!