Issues with shocking for Algae! Please HELP!!!

[frustratedpoolmom]

I think there is a popular belief that shocking will always kill the algae. IT WONT! Sometimes you need an algaecide. Yes your CYA lvl will hold chlorine better at around 80ppm with a SWG.

Also, make sure your not trying to test your water after you shock seeing as how the chlorine lvl is so high that it tends to thow off most testing reagents.

What type of filter do you have and when did you clean or backwash it last. Make sure that when adding something to kill the green stuff that you give the pool a quick brush down to disperse as much of the green stuff as you can. It will make the shock treatment/agaecide or whatever your using that much more effective.

A popular belief?

Algaecide is completely unneccessary in a properly chlorinated and balanced pool.

I have added nothing but bleach to my pool in over 2 years, and have not had a single issue.

I can say that I have personally helped hundreds and hundreds of pool owners clear their algae issues with nothing but chlorine, zero algaecide.

The only test that would really be problematic at high FC levels is the PH test.

 

[duraleigh]

I think there is a popular belief that shocking will always kill the algae. IT WONT! Sometimes you need an algaecide.

Actually, algaecide is not particualry good at killing algae but rather is reasonable at preventing it. (but so is chlorine)

Chlorine kills algae......it's the best thing you can use.

 

[poolpop]

If I am not mistaken typically FC levels above 10 give a false HIGH Ph. Therefore I would assume that your Ph is much lower than 7.0. My thinking is that you need to increase your Ph some or at least enough that you see it go up on your testing to 7.4 or 7.5. Someone else feel free to wade in here.

 

[frustratedpoolmom]

I would agree with you, I just don't want him to overshoot and end up with too high PH. Be conservative in your approach when raising the PH, Matt.

 

[Guest]

I think there is a popular belief that shocking will always kill the algae. IT WONT! Sometimes you need an algaecide. Yes your CYA lvl will hold chlorine better at around 80ppm with a SWG.
Blatantly false. You just have to bring the FC up high enough for the current CYA level. Algaecides, except for copper and halobgen based ones (sodium bromide and inorganic ammonia/EDTA combos) do not kill algae but only inhibit it's growth. Copper kills algae but the cure is worse than the disease, Chlorine and bromine kill algae (and the reason sodium bromide products work is they take CYA out of the loop) but it,too is is often a cure worse than the disease. Monochloramine kills algae (created by either adding anhydrous ammonia to the pool, which is an old time commercial pool maintenance trick or by using one of the inorganic ammonia/EDTA based 'chlorine enhancers on the market after raising the pools pH above 8.0) and also takes the CYA out of the loop but then you have a pool full of combined chlorine to deal with! So,for the most part, algaecides do not kill algae but chlorine (and bromine) does!

Also, make sure your not trying to test your water after you shock seeing as how the chlorine lvl is so high that it tends to thow off most testing reagents.
Also untrue with a caveat. High FC levels can interfere with phenol red pH testing so it's a good idea not to test pH until the FC drops below about 10 ppm but if you are using the recommended drop based kits we talk about in pool school the other tests will be valid. The TA test will not have the green to red color change but rather a blue to yellow color change since one of the indicator dyes will beach out but the results are still valid. The CH and CYA tests will not be affected and the reason we recommend FAS-DPD testing over DPD testing is that it does not bleach out and can test chlorine levels up to 50 ppm with a precision as great as .2 ppm over the entire testing range.

What type of filter do you have and when did you clean or backwash it last. Make sure that when adding something to kill the green stuff that you give the pool a quick brush down to disperse as much of the green stuff as you can. It will make the shock treatment/agaecide or whatever your using that much more effective.

Brushing the pool when killing algae IS very important. Good advice here!

 

[MattGinGA]

Here is another question. With a CYA of 65 the Pool Calculator recommends a FC level of 19ppm to reach and maintain shock level. On the Chlorine/CYA chart however for a SWG it recommends between 24 and 28ppm. Which one should I follow? I'm at roughly 21.5ppm right now and need to know what I need to do.

Matt

 

[duraleigh]

Matt,

One thing you will pick up on soon is your pool will be happy if you are pretty close on your numbers.....you don't have to be absolutely precise (although some folks do, most pools don't :lol: )

That said, I have yet to see anybody post that their pool is a slimey, algae-laden swamp because they put in too much chlorine. So, within reason, keep your chlorine high....go for the 24-28

 

[MattGinGA]

Thanks Duraleigh I appreciate it.

Matt

 

[MattGinGA]

Alright, well today I took the advice I had been given and took the FC level from around 22ppm all the way up to 28ppm. It's been that way for a while and when I just went out and took the filter cartridge out to clean it something happened that hasn't happened before. There was this pile of yellow gunk all in the cartridge. It was thick and almost looked like mustard except it was a little grainy. Any ideas what that was? Was that an indication that I JUST NOW started killing the algae that was in there?

Matt

 

[frustratedpoolmom]

That was probably pollen.

Edit: Reminder - those intex filters are disposable and not meant to be cleaned like a regular cartridge filter. They only last 1-2 weeks under "normal" conditions. When fighting algae you are best to stock up on the filters and just dispose of it when it gets clogged with algae/gunk. I highly recommend you put a fresh one in, if you haven't already, and if you don't have a good supply, go pick up 1/2 dozen or so.

 

[MattGinGA]

Alright! I am seriously getting frustrated now. Is there no end in sight? 3 days ago I posted a picture and here now is a picture from literally 2 minutes ago. Ahhhh!!!!!!!!!!!! Somebody help!!!!

 

[JasonLion]

You need to get a full set of water test results and post them. A picture gives us some clues, but the water test results really tell you what is happening.

 

[frustratedpoolmom]

Hi Matt,

Still keep the FC at 28?

From the pics, it looks to me like the new photo shows more milky-grey tinge which tells me the algae is dying. I think despite how it looks now you are making progress.

 

[duraleigh]

Hi, Matt,

Stay the course and keep your patience. Pools always clear up faster than the time it takes to get them murky! :-D

Test results are very meaningful to the forum and will give us clues if you are getting off track.

 

[MattGinGA]

Alright, here are my test results as of just a few minutes ago. We had a major storm come through that dumped a lot of rain on us last night so I've noticed some things have changed.

CYA - 60
PH - 6.8
FC - 21.5
CC - 0
TC - 21.5
CH - 70
TA - 80

I have a feeling that my filter is designed for simply running once you get the pool to normal. I don't think it was designed to bring the pool out of being winterized and fighting algae. I just don't think it's cutting it. What are your thoughts? It's one of those cheap cartridge filters that comes with the intex pools.

Matt

 

[JasonLion]

Your PH is too low. It is difficult to tell how much too low, because the common PH test reads levels below 6.8 as if they were 6.8 and the high FC level means that the PH will read higher than it really is. Regardless, your PH is clearly too low. I would allow the FC level to fall below 20, preferably to between 10 to 15, and then adjust your PH up to between 7.4 and 7.8 with borax. This is important, since extremely low PH levels can cause chlorine to be ineffective. We don't know for sure if your PH is really that low, but it seems likely.

Intex filters are not as good as larger filters, and can take a very long time to clear up the water after the algae is all dead. Lets be sure the algae is really all dead first, and then think about the filter.

 

[MattGinGA]

I'm tired of working my rear end off keeping the chlorine level up with no improvement. I don't even have a life because I'm constantly having to take care of the pool when I'm home. I'm about to drain it and start all over if nobody has any better ideas.

Matt

 

[frustratedpoolmom]

Matt, I'm sorry you are feeling frustrated and discouraged. I understand. To put it in perspective, its only been about a week, right? Intex filters are just not great at this sort of thing....and there are people tackling algae blooms with regular set-ups that are going longer than you have been.

If you want to drain and start over I guess that's up to you...

Did you try bumping the PH up a bit as Jason recommended, to see if that helped the chlorine be more effective?

 

[Gooserider]

FWIW, when I started using BBB this spring on the green opening swamp, I found that I had several days of murky green w/ little obvious change, and then it went from green to clear in less than a day... Still feel like this season was the fastest and easiest change from swamp to swimmable I've ever done... Now if it would quit raining and warm up enough to make the pool usable...

Gooserider

 

[dattia]

I feel your pain Matt, I drained my pool last year and started over with BBB... it was the greatest thing since sliced bread! Almost effortless after I sorted through a filter problem and got my good test kit. I guess I took its simplicity for granted and didn't close properly. I am now engaged in the biggest pool war of my life. A few days ago, I also was ready to drain, but stuck it out and am now seeing progress. Not as much as I'd like, but enough to keep me going.

Wow...an overnight green to clean sounds a bit like heaven, I'll keep my fingers crossed for your pool and mine!