Advice needed please

jokrswylde · Postby **jokrswylde** » Mon 01 Jun, 2009 09:45

pool has been a nice, cloudy, olive green color for about a month. During the three weeks I have tried using bleach, sodium dichlor, calcium hypo, I have vacced, brushed, raked (all leaves gone), hosed off the filter 2x a day, and have ran the pump continuously.

I have an above ground approx. 12500 gallons with a cartridge filter. Pool stores latest analysis:

Total alk- 120
pH- 7.4
Total Hardness - 130
Total chlorine - 7.5
Free chlorine- 3.8
Cy. Acid - 0 (they think the test messed up somehow)

The guy at the pool store said to stop shocking it ( I have been using granular cal hypo) and just let the filter run. I tried this for the weekend, but no change. I want this water c;ear! Any ideas?

jokrswylde · Postby **jokrswylde** » Mon 01 Jun, 2009 12:43

ok, just had it tested at a different store:

Free Chlorine - 1.4
Total Chlorine -2.9
Combined Chlorine - 1.5
pH -7.6
Cyanuric Acid -569
Total Alkalinity -135
Calcium Hardness -91

He told me to add 11 lbs of pH decreaser, and 13.75lbs of calcium hardness increaser once the pool clears...
To clear the pool, he sold me some expensive algae preventer and remover(12%) copper sulfate. He said he was certain it would work....I was sceptical but bought it anyway. He said not to worry about alkalinity and calcium until I got it clear. Does this seem like sound advice?

Postby **chem geek** » Mon 01 Jun, 2009 16:37

No, it's not really sound advice since it does not get at the root of the problem which appears to be that you have a very high Cyanuric Acid (CYA) level. This makes chlorine ineffective. So while it is true that dumping in copper ions will kill the algae, it will also leave your pool filled with copper that can stain if overdosed or if the pH goes up. It will also turn blond hair yellow-green. That's not a good situation.

Since you have to dilute the water through water replacement to lower the CYA anyway, I'd just do that first through many multiple partial drain/refill or through continuous drain/refill. Unless the algae is getting a lot worse quickly (and I doubt that since it's already been cloudy green for a month) then just do the water replacement and keep at least some chlorine in the pool, but do NOT use either Dichlor or Trichlor. Use chlorinating liquid, 6% unscented bleach, or since you CH isn't high you can use Cal-Hypo. Remember the following three chemical facts that every pool store should be telling their customers and that should be on the labels of products:

For every 10 ppm Free Chlorine (FC) added by Trichlor, it also increases Cyanuric Acid (CYA) by 6 ppm.
For every 10 ppm FC added by Dichlor, it also increases CYA by 9 ppm.
For every 10 ppm FC added by Cal-Hypo, it also increases Calcium Hardness (CH) by 7 ppm.

Finally, I would NOT trust the pool store results. You should get your own good test kit, either the Taylor K-2006 you can get at a good online price here or the TF100 kit from tftestkits.net here with the latter kit having 36% more volume of reagents so is less expensive per test. Also, read Defeating Algae to learn how to clear your pool after you've lowered the CYA level and see this link to see how a pool can be cleared of algae by chlorine alone.

Richard

jokrswylde · Postby **jokrswylde** » Tue 02 Jun, 2009 08:53

typo...c.a. is 69, not 569..does that change the advice?

Postby **chem geek** » Tue 02 Jun, 2009 12:50

That's a lot better, but at a CYA of 69 ppm you can't have the Free Chlorine (FC) level get below 3 ppm or else algae can grow and a reasonable target FC for that CYA when manually dosing is 5 ppm or so. The reason for the algae growth is that the FC was too low for that CYA level.

So you don't have to do a partial drain/refill unless you continue to plan to use stabilized chlorine (Trichlor or Dichlor) in the future. If you don't dilute the water, then the shock level of chlorine is somewhat over 25 ppm FC. That means hitting the pool hard with unstabilized chlorine -- chlorinating liquid or 6% unscented bleach. You can also use Cal-Hypo. Just be sure that with Cal-Hypo you pre-mix it in a bucket before adding it and with any of these chemicals add them slowly over a return flow with the pump running and then lightly brush the side and bottom of the pool where you add it to ensure thorough mixing. Use The Pool Calculator for figuring out dosing.

The key is to add chlorine and then keep adding it to get the FC level up high. It sound like you've just been adding it once in a while, but you need to hit it hard -- take a weekend day, start in the morning, and check every hour the FC level and if it drops, raise it by adding more chlorine. Obviously you have to have a test kit with a FAS-DPD chlorine test to measure chlorine at high levels such as the ones I suggested.

You should also try to physically remove some of what is in the pool if it's more solid -- use a shirt over a pool net and use a skimmer sock in the skimmer.

Please read the links I gave on defeating algae. You need to decide what to do. There's nothing wrong with you just following pool store advice. It's your money.

Of course, you can just go with the copper algaecide since that will kill the algae, but then you'll have a potential copper problem (staining) to deal with. The main reason for the pool store's suggestion of using acid to lower the pH further was that the Cal-Hypo would increase the pH and if you had copper in the water then it would likely stain at higher pH.

Richard

jokrswylde · Postby **jokrswylde** » Tue 02 Jun, 2009 17:11

24 hours after adding the copper algae killer, no change noticed. Using the pool calculator, it said I should add 7.8 oz of cal-hypo. I have a 1 lb bag, will that be sufficient to do the trick, or,

going by what you said about taking a full day, would you recopmmend buying a 5lb bucket of cal-hypo and adding it periodically over the course of one day?

Postby **chem geek** » Wed 03 Jun, 2009 11:48

Yes. You need to maintain the shock level of chlorine. If you add enough chlorine, the dark green should turn gray. Then it takes days for this to get cleared up. See the pictures in this post for an example and follow the instructions in Defeating Algae or the more detailed instructions in Turning Your Green Swamp Into a Sparkling Oasis.

jokrswylde · Postby **jokrswylde** » Wed 03 Jun, 2009 16:20

pool store gave me phospate remover. Said that algae could not live unless they had phospahes. Will this help???????????? Am going to wait for advice before adding this as I am not sure these people at the store know what they are talking about!

Postby **chem geek** » Thu 04 Jun, 2009 02:03

Phosphate removers are like algaecide in that they will either kill or prevent algae, but at extra cost. It won't clear your existing algae and since it takes chlorine to do that and since chlorine will also kill the algae, then chlorine alone is all that is needed, but if you don't want to bother with managing your Cyanuric Acid (CYA) level, then a phosphate remover is one (expensive) way to do that. You will need to be able to vacuum to waste since the phosphate remover will precipitate the phosphates in the water (and if you had your filter running it could clog the filter).

So do whatever you want. I've given you the link to the most straightfoward approach. There are many solutions. You could use a copper algaecide since that will also kill algae, but can also cause staining. You've already added it and didn't notice a difference with the algae, but it did probably prevent them from growing. A phosphate remover would be similar -- it will stop growth, but won't kill (oxidize) existing algae. Chlorine will oxidize the algae turning it from green to gray and eventually clearing.

jokrswylde · Postby **jokrswylde** » Thu 11 Jun, 2009 17:20

: pool1.jpg (48.75 KiB) Viewed 4614 times

: pool1.jpg (48.75 KiB) Viewed 4614 times

Don't know if these pics help at all. but here is what I am dealing with after adding 10 lbs of cal-hypo over the course of las saturday to maintain shock level. Shock level is currently staying around 10 ppm, ph is good, but I still can't see halfway to the bottom. Filter has been running continously with me cleaning the cartridge every time psi goes up to 12. The water has certainly changed from very green to a more grayish/olive color. I have since added 5 more lbs of cal-hypo....not sure how anything could be living this water.

Anyway, should I just hold off adding anything else and give it a few days? Runnin g out of options and would like to at least be able to swim by the 4th of july. Thanks for the advice so far.

Postby **chem geek** » Thu 11 Jun, 2009 21:15

With a Cyanuric Acid (CYA) level of 69, the shock level of chlorine is around 25 ppm FC or so. It will take a lot longer to clear at 10 ppm FC so I'd suggesting raising the FC to the appropriate shock level. Turning from green to gray is normal. See this link for a pool getting cleared of algae using chlorine alone. Read Defeating Algae again and follow the advice there -- you simply are not using a high enough level of chlorine and have a lot to clear up in the pool. It didn't just take a few days to get in the bad shape that it's in and will take more than a few days to clear it.

Be aware that with Cal-Hypo, every 10 ppm FC that you add also increases the CH by 7 ppm. You never measured Calcium Hardness (CH), but your Total Hardness is low enough that CH is probably fine for using Cal-Hypo, at least for a while. You could also use chlorinating liquid at some point if the CH starts to get too high. You'll only know that if you get the proper test kit as I suggested.