Low ph and algae

[cdingess]

I shocked my pool due to what I think was algae at the bottom. When can I algaecide 60? Also, I always have a low ph. Please help.

[Watermom]

We need a lot more information to be able to advise you.

1. What kind of pool is it? What is the volume?
2. What size pump and what kind and size of filter?
3. Exactly what all have you added to the pool, meaning ingredients and not just product names like 'shock.'
4. What does the water look like?
5. Do you have a drops-based test kit? If so, what kind? Post current numbers.

If you don't have a good drops-based test kit:
The test kit that we think is by far the best is the Taylor K2006 or 2006C (better buy). Not available locally but you can get it through this link that takes you to Amazon: http://pool9.net/tk/

But, in the meantime, go to Walmart and see if they have the HTH 6-Way drops-based kit (no test strips!) and get that. If they don't, get an OTO/Phenol Red kit (yellow and red drops) instead. Use it to test and then post your numbers. Also while you are at WallyWorld, get several jugs of their generic 8.25% bleach and a couple of boxes of 20 Mule Team Borax (laundry aisle).

Repost with requested info and then someone here can try and help you.

(Until you registration is completed, you won't be able to see the rest of the forum while you are logged in. So, copy that link and then paste it into a browser window after you log out.)

[cdingess]

Here are my numbers from my kit ph 6.8 oto 10 alk 40 hardness 80 cya 41.

I shocked with hth yesterday and used algaecide 60 11oz last week Wednesday and Tuesday last week I used shock hth. My filter is 150 sq ft cart filter it's 24-26 above ground pool. The water never got green-green but had green spots. I vacuum e them up and a day or two they come back. I put less than half box mule to raise the ph up. It holds 16000 gallons. I have purchase all that you have told me too. I was using the test strips but will stop. I am using the floater with 3 inch chlorine tabs.

As of today 7-614 I shocked yesterday and vacuumed yesterday and put some mule in.
What else can I do to prevent that coming back??! Please help. Christina

[PoolDoc]

If you're pool is 26' x 4', the volume is ~14,000 gallons. If it's 26' x 4.5' (54"), it's ~15,000 gallons.

Do this:

1. Check the chlorine again. If the level is greater than 5.0 ppm, you'll need to get a gallon of *DISTILLED* water are Walmart. Mix 1/2 of pool water with 1/2 cup of DISTILLED and retest the pH of the mix. If you use DISTILLED (not bottled, spring, etc.) your pH reading should be about accurate. The problems that high chlorine can screw up phenol red pH testing.

2. Your pH is too low. A pH reading of 6.8 may mean 6.8 . . . OR, it can mean anything below 6.8, such as 5.0 which will damage your liner rapidly. Add 1 box of borax at a time, to the skimmer with the pump running. Do NOT remove the skimmer basket. Retest your pH after 2 hours of pump run time. Continue adding borax until the pH is 7.0 or greater. (Keep up with how many boxes of borax you add - it may matter later!)


The water never got green-green but had green spots. I vacuum e them up and a day or two they come back.
3. You're describing mustard algae. It's VERY chlorine resistant. This page covers some more details => http://pool9.net/algae-m/.

4. Meanwhile, each time it re-appears add 2 gallons of bleach in the EVENING and then brush all the spots.

5. Polyquat (algaecide 60) is not particularly helpful with mustard algae. It certainly won't hurt, but won't fix the problem, either.

6. Question: are you near open water? (I'm trying to figure out why some pools are prone to mustard algae, and others aren't.)

Post your results from pH testing, and let us know what you think after you read about the mustard algae options.



4. Retest your alkalinity, once you get your pH above

[cdingess]

Ok I did what you said and my ph is now 7.5 after 1 box boraxe yay!!!! The oto was >5 so I put 2 gallons of bleach in. I'll check both tomorrow evening. Hopefully it's all gone. Also, I do have a large pond in the property. I haven't had the solar cover on the pool since this all began, would it be safe to put on if I hear it's going to rain? Thanks Christina

[PoolDoc]

Yes, you can cover it. But make sure 10 - 20% of the pool remains uncovered.

When you are removing 'goo', including algae, volatile chlorinated compounds form ('stinky' chlorine). They can't leave a fully covered pool.

And . . . be SURE to keep the chlorine high during the rain; algae often gets ahead of pool owners when it's raining, because the pool gets ignored.

[cdingess]

Should I check my numbers daily even if I don't see algae just for preventive or stick with strips?

[Watermom]

You already know what we are going to say to that question. Yes! Test chlorine and pH daily. If you do so and keep your chlorine levels where they need to be, you won't get algae in the first place! No 'guess-strips.' Get a Taylor K2006 kit or 2006C (better buy). You need it to manage your pool properly. It isn't available locally but you can get it through this link:> http://pool9.net/tk/

[cdingess]

Thank you thank you thank you!!!! Hopefully algae will be gone!

[cdingess]

Man this difficult. Ok my ph is 7.5 my oto is orange with my test kit and I still had 2-3 small spots of algae so I put 2 gallons of bleach in after vacuming the pool. Now how do I treat orange oto or is that ok due the bleach from yesterday?? Christina

[Watermom]

If your OTO test showed orange, then you didn't need to add more bleach. Take a look at this chart:> http://pool9.net/oto-chart/

It will come down in time, but from now on if your OTO is orange, you don't need more chlorine. You don't want to bleach out your liner.

[cdingess]

My oto was bout 9 on your chart. Hopefully the algae spots are gone thank you so much. Do I need to do the shock stuff every week like the package says even if I'm having no problems? Also, should I continue to out in the algaecide 60 in after I get my numbers to normal? It didn't help before just wondering. Since I got the algae this early is this something I will always have to watch out for now or do you think I KILLED it? And I do have a large pond kind of close to pool. Thanks again for all of your great knowledge.

[cdingess]

Is it safe to swim in with high levels oto orange? I just check levels this morning after 4 gallons total and it's pretty close to 25 and ph 7.8??? I think I over did it????? I didn't want algae. I didn't see any but I want to keep my liner too. Geeze. Please help again. Christina.

[cdingess]

Please disregard the oto. The next message has the more current numbers.

[PoolDoc]

OTO orange is high. If your CYA is low (less than 50), it is definitely high enough to bleach out swimwear. It won't hurt people, but again, if the CYA is low, it will dry skin and make eyes sting. (Also seems to help with acne, if that's an issue for anyone among your swimmers ;) )

It's really hard to be more specific without knowing your CYA level -- that's one reason we push the K2006 so hard.

OTO orange is also high enough to bleach liners -- sometimes. I haven't actually seen Intex pools that have been bleached, so their liner prints may be resistant. In any case, liners themselves aren't damaged by high chlorine; just the printed colors on top of the liner.

But again, we really can't offer better advice till you have better test results.

Good luck!

[cdingess]

My cya 55-60 with orange oto and ph 7.8 but algae is gone for now. Is all this safe? Sorry for all the post I'm a nobbie to this site. Christina

[PoolDoc]

Perfectly safe; may be hard on swimsuits and treated (dyed, permed) hair.

It *may* dry your skin or or sting your eyes.

OTO orange actually covers a range from 20 - 40 ppm, so it's hard to tell much more.

But I can tell you that a number of years ago my older son (and about 40 other senior swimmers in Chattanooga) spent a summer practicing in an outdoor pool with CYA => 30 - 50 ppm and FC => 20 - 40 ppm. This was 5 days per week, 2 - 3 hours per day. They lost a lot of swimsuits*; the girls didn't have to shave their legs; the guys who didn't wear caps (including my son) had their hair turn sort of an ash color. It didn't affect their eyes -- but they all wore goggles. My son and another guy had 'goggle stripes' where the hair under the goggle strap retained it's original dark color! But, with over 200 hours of actual water time, nobody experienced any skin problems, etc. (The City of Chattanooga pool operator didn't understand how ORP controllers worked, and wasn't taking advice. I monitored the situation since it affected my son, but didn't raise a fuss.)'

[cdingess]

This my sound silly but my oto is still orange 25 and ph 7.2 should I add chlorine tab to the floater? I have about 50% of one in there now or do I let it dissolved completely while the oto is still high? Christina

[Watermom]

Let the one dissolve that is in there now. How many more do you have left? Are they wrapped or unwrapped?

[cdingess]

I have a lot left medium size bucket and unwrapped.

Should I be using a ph stabilizer or do I wait till oto I'd yellow?

[PoolDoc]

Do you mean chlorine "stabilizer"?

You probably should NOT add any chlorine stabilizer, since you already have adequate levels, and since simply using tabs adds quite a bit.

[cdingess]

My oto is finally less than 25 its finally yellow and ph 7.2 but I think the algae came back but a little bit. I had small spots on bottom of pool just where pool curves to bottom?

I don't know what to do? Should I put more bleach in or put chlorine tab back in? Other than that the water is very clear, just spots starting up.

Please help.

[Watermom]

How much less than 25ppm? You really need to bite the bullet and get the good Taylor K2006 kit that we have suggested three or four times within this thread. It is very difficult to help you without you having the ability to have good CYA and chlorine numbers.

Brush the pool while the chlorine is high.

[PoolDoc]

Are you brushing the pool?

Physically disturbing the algae is necessary to break up the protection layers that the biofilms create. Other than consistent high chlorine PLUS brushing, the other treatment options are not super attractive.

=> Copper algaecides, at high doses work. But they also stain and turn hair green.

=> Ammonia based mustard products also work, but leave you with a downstream clean up mess -- very high combined chlorine.

The remaining option is what I'm currently testing: very low phosphate levels. But there are games going on with the concentration of the products. Currently, the only reliable product seems to be the Orenda PR-10000 product, which is not widely available. None of the major online distributors have it, probably because it makes their favored products look bad. Here's a listing from Google Shopping (https://www.google.com/shopping/product/6194551360558548901?q=orenda+pr10000).

To use it, you ALSO have to get the Taylor K1106 Phosphate kit (http://www.amazon.com/exec/obidos/ASIN/B003V4QUDI/scouscho-20/) . But it appears you haven't even gotten a K2006 . . . so for whatever reason, so I'm guessing this is not an option for you.

================================================== ====

I think we're out of options here. I'll admit the choices aren't great, but they are what they are, and talking about them longer isn't going to change anything. Honestly, if your budget is too tight to allow you to get a K2006, it's probably too tight to deal with mustard algae, no matter what direction you go in.

You may be better off simply covering the pool, and adding chlorine underneath. After a couple of weeks at 20 ppm and no light, the algae will almost certainly be dead.

But I think we've done all we can do.

Sorry!

[cdingess]

How much less than 25ppm? You really need to bite the bullet and get the good Taylor K2006 kit that we have suggested three or four times within this thread. It is very difficult to help you without you having the ability to have good CYA and chlorine numbers.

Brush the pool while the chlorine is high.

It was 9. Can i buy the Taylor K2006 at a pool store so i don't have to wait for it in the mail? I thought the one from wal-mart was ok for checking chlorine and ph. I didn't know the Taylor kit was a must, i just want this stuff gone. I have been brushing the pool as well. I don't put the cover on at all even if rain is coming. Could that be the cause of this?

[PoolDoc]

You can try. Usually what happens is EITHER they don't have it at all OR they will try to sell you the K2005. It's not.

Order it from Amazon. If you can buy directly from Amazon, do so. If only 3rd party sources are available, give Amato preference.

Fixing this is going to take time, and if you get in a hurry, you'll simply become a pool-store victim, again.

[cdingess]

Ok I'll order it but till then should I keep the chlorine high at 9, 13, 25? This morning is was 9 ph 7.2. No green spots

[cdingess]

You were correct they did not have the Taylor 2006 kit, but I did take them a sample of my water. These are the numbers they gave me TDS 500 cya 82 tot chlorine 7.5 free chlorine 7.5 ph 7.8 tot alk 53 adj alk 28 tot hardness 163 a and no to black green mustard algae. I had them check my phosphates they are ok they said. Also they didn't talk me into anything. Thanks for the tip. Should I add chlorine tab to floater till kit comes or keep with bleach? This morning I used bleach. Thank you for all your help.

[Watermom]

Use bleach.

[cdingess]

The kit should be in by July 21-23 😎. Thanks again

[Watermom]

Good deal.

[cdingess]

My kit is in. A few green spots yesterday. I brushed and vacuumed yesterday. Chlorine look 6 with old kit. I'm ready to rid this algae forever. Please help.

[PoolDoc]

Watch the videos, run the tests, and report the results . . . and we'll see how we can help.

[cdingess]

I didn't get videos. I followed the box instructions. These are what I have:
Chlorine. 4.8ppm
No com chlorine it stayed clear
Ph 7.2
Alk. 350
Cya 75 ppm

I hope these results help.
Christina

[Watermom]

Here is a link to the videos:> http://pool9.net/K2006-vid/

[PoolDoc]

CH level?

With algae, and a CYA level of 70+, you need to maintain FC levels of 15 - 20 ppm. If you have mustard algae, even higher levels are required.

Watch the videos, and redo any tests you overlooked or might have done incorrectly: FC, CC, pH, TA, CH & CYA.

[cdingess]

I watched the videos. Thanks that was help. I redid test.
Cl 5.6 ppm
Com cl 0 stayed clear
Ph 7.3
Alk 100
Hardness ca. 125
Cya 75

I have 3 gallons of bleach here and 2 boxes borax and 1 box baking soda

[PoolDoc]

Good!

Then you just need to adjust your chlorine upward, hold it there, and brush regularly.

Normally, your chlorine level should be 10% of your CYA level (7 ppm). When you are dealing with algae, you'll need to go to 20% (15 ppm) or higher and HOLD it there, till the algae is gone.

Physically brushing the pool surfaces, to break up the self-protective layer of slime that algae colonies produce, is VERY important. Chlorine does NOT penetrate slime well. Some other algaecides (monochloramine, copper) penetrate much better, but at the cost of some serious side-effects.

A gallon of 8% bleach contains the equivalent of about 0.7 lbs of chlorine gas (100% available chlorine). Your PF is 8, so each gallon will add a little less than 6 ppm of chlorine (0.7 x 8 = 5.6) to your pool.

Most dichlor is 61% available chlorine, so a pound of dichlor would add about 5 ppm (0.61 x 8 = 4.9) of chlorine and about 4.5 ppm of CYA to your pool.

[cdingess]

How much bleach would you suggest? How long do I keep it that high? Just till it's dead or much longer? Should I stay with bleach after this or go back to my unopened tab? Sorry for the questions never had this before and don't want it again.

[cdingess]

Which works quicker in killing this the 6 gallons of bleach or 5.5 tabs? Of course with me brushing and cleaning

[PoolDoc]

It takes days for trichlor to dissolve, so the bleach.

[cdingess]

Do I put all 6 bleach in at on time or do 2 then check clorine?

[PoolDoc]

I would go step by step -- there is some risk of bleaching your liner. There are no real guidelines on this topic, unfortunately. Some liners are unaffected by even extreme levels of chlorine; others are bleached by even low NSPSI / NSPF (standard) levels -- and I have not been able to discover any method of distinguishing one from the other, till it's too late.

[cdingess]

Ok. Thank you. 😎

[Watermom]

You cannot shock a pool with trichlor tabs.

You want to maintain this high chlorine level until you meet 3 criteria:
1) You can go from sundown one evening to within an hour of sunrise the next morning without losing more than 1ppm of FC.
2) You have no higher than 0.5ppm of CC
3) Your water is clear and there are no visible algae spots.

Then, keep it high for one additional day for added insurance and then let it drift back down. At that point, you need to keep your chlorine level between the minimum and maximum based on your CYA level. http://pool9.net/cl-cya/

[cdingess]

Numbers as of today.
Cl 16.4
Ph 7.5
Cya 75
How do I keep my clorine at that number to kill the algae? Besides doing the usual cleaning, brushing, and vacuuming. I have 2 tabs in the floater and have been checking the chemicals daily in the moring. Is there something else I need to add? Should I add more bleach? There was 1 small spot of green in pool yesterday and the sock on skimmer basket was slight green this morning.

[Watermom]

This thread is really long and I don't have time to scroll back through searching. Easier to just ask. Do you have a K2006 kit? I'm assuming you do with a reading like "16.4." If not, what kit are you using? Please update your signature by clicking on the link in my signature to say what kind of kit you have.

[cdingess]

I do Have the k2006 kit.

[Watermom]

I just quickly scanned this entire thread. I think we have pretty much given you the information to clear this. Now, what is needed is consistency on your part. If you go back and read this thread you will find the things you need:
-- the chart with the CYA/chlorine connection which tells you the levels to keep your chlorine at
-- the dosing suggestions that Ben gave you.
-- the criteria for knowing when you are finished
-- the demo videos to help you know how to use the kit

I will also tell you that in your pool, each quart of 8.25% bleach will add about 1.5ppm of chlorine and each of the 121-oz bottles will add about 5.5ppm. When you test in the evenings, add enough bleach to get back to shock level. Keep it at shock level until you can meet the 3 criteria listed in one of the posts above. Also, continue brushing while the chlorine is high.

If you do these things consistently, your pool will clear.

(Also, use the 10mL water sample instead of the 25mL one when you test. It will make your testing reagents last longer. You will multiply the number of drops by 0.5 instead of 0.2.)

You might want to also read this thread:> http://www.poolforum.com/pf2/showthread.php/24509-What-can-I-do-with-old-pool-chlorine-and-chemicals

Your CYA is already high enough but you still have all those unwrapped tabs left over. The linked thread discussed what to do with leftover chemicals. Sometimes, it is best to just go ahead and use them up even though your CYA will continue to rise and you'll have to use higher chlorine levels to compensate for the rise.

Good luck! :)

[cdingess]

Thanks for all your guys help!! I just wanted to makesure I was doing this correctly. 😎