Persistent Dead Algae

[incredible-bulk]

Hi guys.

I have a temporary above ground pool. Last year, I believed my sand filter was letting in sand to the pool. I vacuum this to waste but the cycle repeated. I decided to upgrade this year to a much bigger pump and sand filter to replace the less powerful one I also believed to be a broken.

To cut a long story short. I have been having the exact same issue. I started to think it was the sand was too fine or something. I have only in the past days come to terms with what I am seeing is algae and not sand.

I was having an issue with combined chlorine a few weeks ago. I couldnt see any signs of algae, the water was crystal clear. I posted on here and someone suggested i had algae somewhere. Sure enough, i had some puffs of green when i brushed right in the folds where the side wall meets the base of the pool. I slammed the pool, have passed the overnight test and since then have always kept free chlorine on the high limit of ideal…

Dead algae continues to settle on the bottom and there are no sources of algae remaining in the pool. I had to replace the steps so even the ones I have are brand new. There is nothing else in the pool that i havnt scrubbed religiously. My combined chlorine is down to 0.05ppm from being above 1ppm and free chlorine sitting between 5 - 10ppm on any given moment.

The only thing i can think of is a bit mad but the vacuum hose i use to vac the pool. Whenever I submerge the hose to prime it so that there is no air being sucked into the pump, as the water reaches the end there always seems to be a bit of green coming from inside the hose? Is this a thing? If algae can grow in a vac hose and if that is potentially my source of dead algae coming to rest on the bottom, how do i prevent it? What can i do to stop this cycle?

Cheers.

For clarity:

FC: 5.45ppm (lower end just before adding daily dose of chlorine)
CC: 0.05ppm
pH: 8.0 (gradually risen to 8 over the past week, it just does this no matter what)
TA: 75ppm
CH: 207ppm
CYA: 45ppm

 

[wireform]

For starters how are you testing water? Let's say you're testing on your own with one of these kits
Test Kits Compared just so you know if CYA is more then a whole number such as in your case 40 then call it CYA 50. So now that's taken care of, the FC/CYA Levels chart says target for your 50 is 6-8 so your pool is clearly skirting with danger all the time of growing algae. Next,
SLAM Process is commenced with
Overnight Chlorine Loss Test which has the 3 criteria rule which one of them is no algae dead or alive so clearly you weren't finished therfore you have reoccurring algae and will always have until things change. And while you at it read
Pool Care Basics.

 

[incredible-bulk]

Hi thanks for your reply.

I am using photometers to test my pool water because that is what I have and you cant get taylor tests here. I know my test results are incredibly accurate. The only one at the moment that is open to interpretation is the CYA because i have been unable to source the reagent for my photometer and thus have been using a palintest dot in a tube test which i believe to be exactly like the taylor one. I have it between 40 and 50 so called it 45. I just changed the CYA in pool math from 45 to 50 and it didnt change my recommended FC levels so they are what they are whether its 45 or 50. The recommended FC levels stated are between 4-8ppm and I have been keeping it slightly above that for weeks. I have been measuring daily and its not been below 5ppm for weeks now. I top it up to 9-10ppm daily depending on the daily demand.

I did a SLAM previously because i had CC around 1.4ppm. I stopped the SLAM after I met the criteria. At the time, i believed it was sand on the bottom. Anyhow. My test results are not indicative of algae growing in the pool. My CC was virtually zero last night at 0.05ppm. I believe i am introducing algae every time i try and vac the dead algae off the bottom from algae potentially being in the vac hose and thus in this constant cycle.

Dead algae on bottom -> vac to waste -> tiny bloom of green from the vac hose when i prime it -> this is killed right away because of FC being high enough -> dead algae finally settles on bottom and thus the cycle repeats.

I guess what I want to get to the bottom of is what would you do if you suspected algae in your vac hose? What could you do to prevent algae growing there? Even if it is not what is causing my dead algae issue, the green bloom every time i prime the hose is disconcerting for me. How can i prevent that?

Cheers.

 

[wireform]

If you think it's the vac hose the suspended it so it can drain completely but I have never run it that problem. If you brush twice daily and get the dead algae propelled and waterborne it'll end up in the filter and get stuck there.

 

[Bperry]

Hi thanks for your reply.

I am using photometers to test my pool water because that is what I have and you cant get taylor tests here. I know my test results are incredibly accurate. The only one at the moment that is open to interpretation is the CYA because i have been unable to source the reagent for my photometer and thus have been using a palintest dot in a tube test which i believe to be exactly like the taylor one. I have it between 40 and 50 so called it 45. I just changed the CYA in pool math from 45 to 50 and it didnt change my recommended FC levels so they are what they are whether its 45 or 50. The recommended FC levels stated are between 4-8ppm and I have been keeping it slightly above that for weeks. I have been measuring daily and its not been below 5ppm for weeks now. I top it up to 9-10ppm daily depending on the daily demand.

I did a SLAM previously because i had CC around 1.4ppm. I stopped the SLAM after I met the criteria. At the time, i believed it was sand on the bottom. Anyhow. My test results are not indicative of algae growing in the pool. My CC was virtually zero last night at 0.05ppm. I believe i am introducing algae every time i try and vac the dead algae off the bottom from algae potentially being in the vac hose and thus in this constant cycle.

Dead algae on bottom -> vac to waste -> tiny bloom of green from the vac hose when i prime it -> this is killed right away because of FC being high enough -> dead algae finally settles on bottom and thus the cycle repeats.

I guess what I want to get to the bottom of is what would you do if you suspected algae in your vac hose? What could you do to prevent algae growing there? Even if it is not what is causing my dead algae issue, the green bloom every time i prime the hose is disconcerting for me. How can i prevent that?

Cheers.

The photometer tests seem to not have a great track record so there’s that as a possibility. Does the FC test give you an accuracy range?

The SLAM should continue until all the dead algae is gone, including any coming in through your vacuum hose. Would recommend going back to SLAM with the vacuum hose and let the water cycle through it for a while, even if not actively vacuuming.

 

[incredible-bulk]

The photometer tests seem to not have a great track record so there’s that as a possibility. Does the FC test give you an accuracy range?

The SLAM should continue until all the dead algae is gone, including any coming in through your vacuum hose. Would recommend going back to SLAM with the vacuum hose and let the water cycle through it for a while, even if not actively vacuuming.

Free chlorine is accurate to +/- 0.03ppm

 

[Bperry]

Free chlorine is accurate to +/- 0.03ppm

I mean the range. If it only goes up to 12ppm, a SLAM isn’t possible with that device. Is it the style with a dip strip that gets inserted into the photometer?

 

[incredible-bulk]

I mean the range. If it only goes up to 12ppm, a SLAM isn’t possible with that device. Is it the style with a dip strip that gets inserted into the photometer?

No, it uses an adaptation of the DPD method and measures the colour variation of a 10ml sample through a glass cuvette. It measures up to 10ppm but I can measure higher levels by diluting the sample by a ratio with distilled water and the multiplying the result by the dilution ratio. I lose some accuracy but only in the thousandths of a ppm.

 

[Bperry]

No, it uses an adaptation of the DPD method and measures the colour variation of a 10ml sample through a glass cuvette. It measures up to 10ppm but I can measure higher levels by diluting the sample by a ratio with distilled water and the multiplying the result by the dilution ratio. I lose some accuracy but only in the thousandths of a ppm.

I think some users outside the US can get Taylor drop based kits from clear choice labs. I wonder if that’s an option for you? The issue will be no one at TFP trusts anything other than those recommended kits because the others have proven to not be reliable. So you’re kinda limited in the help you’ll be able to get. Giving advice based on bad test data can cause big problems. The pool stores also have similar photo metric test equipment that’s likely even more sophisticated and they get things wrong more often than not. That’s the reason for the skepticism.

If you can find a way to do a good CYA test if you suspect yours is not adequate, that’s a key to your chlorine requirements and SLAM process so finding a way to import one of those would be a good thing to try.

 

[incredible-bulk]

My test results are far more accurate than any drop test kit. I can replicate them, dilute them with distilled water and they all still correlate. The only test I have that is slightly iffy is the CYA one and thats only because seeing the dot is subjective. The measure is a there or thereabouts. Im pretty sure that test is the same as in the Taylor kit anyhow. I feel that we have got a bit side tracked here. I was more asking for advice or experiences of people having algae build up in their vac hoses between uses?

 

[Bperry]

My test results are far more accurate than any drop test kit. I can replicate them, dilute them with distilled water and they all still correlate. The only test I have that is slightly iffy is the CYA one and thats only because seeing the dot is subjective. The measure is a there or thereabouts. Im pretty sure that test is the same as in the Taylor kit anyhow. I feel that we have got a bit side tracked here. I was more asking for advice or experiences of people having algae build up in their vac hoses between uses?

My advice above was on the hose…You need to run chlorinated water through it. You might try priming the hose by inserting one end into the water slowly and allowing the hose to fill with water until you get to the other end, then attaching that end to to the suction port. That way dirty/stale water doesn’t get blown back into the pool.

I mean this in the nicest way possible that your test equipment is not as accurate as you believe it to be. So many people around here have been down that road with those things and been burned by them. Maybe someone else can explain the details of why that is, but the recommendation would be not to trust it.

 

[Donldson]

My test results are far more accurate than any drop test kit.

No, they are not. If you actually think that a DPD solution can indicate FC to a precision of 0.03 ppm then you're buying in on a sales pitch and not reality.

Is your intention to fix the problem or to sell us on the quality of a tester?

 

[incredible-bulk]

I am not here to sell you the quality of my test kit but everyone on here keeps telling me to get a drop test kit that I cannot get where I live. I can replicate my test results over and over. I can use the "effects of adding" function on pool math and then in half hour get the exact test results or very very close to it to a negligible difference. Its not me selling the quality of my tester, its me having to justify the results as accurate and keep being told they are inaccurate based on nothing other than they are not taken with a Taylor kit.

 

[Donldson]

Its not me selling the quality of my tester

Yes, it is. We're telling you that we do not trust your testing and you're telling us that we should.

We don't trust your tester. Period. So far your post history is nothing but telling people why you're not going to listen to their advice. You use cal-hypo. You use inaccurate photometers. If you're not going to listen to out advice, why even ask?

 

[incredible-bulk]

Why is cal hypo an option in pool math if it isnt to be used? You cant buy a FAS DPD test kits in the UK yet everyone keeps offering advice to get a FAS DPD test kit. Cant even get one shipped from another country to here. You can tell me as much as you like that you dont trust my test results but it is the best ive got and I cannot get anything better here. I have a whole load of tests, chemical additions based on pool math "effects of adding", I get replicable results time and time again so I do not have to justify them to anybody. You cant even tell me what test results I have had that are "suspect", just that you dont trust them at all based on nothing. Cheers for the help.

 

[Bperry]

Why is cal hypo an option in pool math if it isnt to be used? You cant buy a FAS DPD test kits in the UK yet everyone keeps offering advice to get a FAS DPD test kit. Cant even get one shipped from another country to here. You can tell me as much as you like that you dont trust my test results but it is the best ive got and I cannot get anything better here. I have a whole load of tests, chemical additions based on pool math "effects of adding", I get replicable results time and time again so I do not have to justify them to anybody. You cant even tell me what test results I have had that are "suspect", just that you dont trust them at all based on nothing. Cheers for the help.

Hoping to help here, really. Cal hypo is ok to use as long as your water can tolerate more calcium in it. The issue with using it over time is that as the calcium builds up, it causes scaling and can damage some equipment and the only way to get rid of it is to drain the water and replace it, which has its own set of problems and risks. Just like trichlor pucks are just fine for use short term until your stabilizer level becomes too high, then same problem as the calcium. Using sodium hypochlorite just adds salt and water to the water so it along with the SWCG, are the two recommended methods of chlorination.

The test method is different though, a huge part of TFP even existing is because bad testing from pool stores (with fancy photo metric equipment) has driven so many people to have trouble and seek a solution. If a better test method existed, I think TFP would adopt it. I don’t mean to beat you up about it, it’s just that I’ve read of so so many people that come here with a problem insisting all their test results are accurate and so the problem CANNOT be with their testing, spend a bunch of money on junk solutions, then once they test again with a better kit find out it was the testing results that are the problem. Just hoping to save you from all the frustration and money spent. Maybe some members from the UK can help with some advice on where to get test kit for others who might see this thread.

I do wish you the best of luck though. Having algae in your vacuum hose indicates insufficient chlorine during use or maybe stored wet without a way to dry out.

Edit: I checked and TFP has a link where you can buy a Lamotte fas-DPD kit in the UK.

Pool Test Kits - Further Reading

www.troublefreepool.com

 

[incredible-bulk]

Hoping to help here, really. Cal hypo is ok to use as long as your water can tolerate more calcium in it. The issue with using it over time is that as the calcium builds up, it causes scaling and can damage some equipment and the only way to get rid of it is to drain the water and replace it, which has its own set of problems and risks. Just like trichlor pucks are just fine for use short term until your stabilizer level becomes too high, then same problem as the calcium. Using sodium hypochlorite just adds salt and water to the water so it along with the SWCG, are the two recommended methods of chlorination.

The test method is different though, a huge part of TFP even existing is because bad testing from pool stores (with fancy photo metric equipment) has driven so many people to have trouble and seek a solution. If a better test method existed, I think TFP would adopt it. I don’t mean to beat you up about it, it’s just that I’ve read of so so many people that come here with a problem insisting all their test results are accurate and so the problem CANNOT be with their testing, spend a bunch of money on junk solutions, then once they test again with a better kit find out it was the testing results that are the problem. Just hoping to save you from all the frustration and money spent. Maybe some members from the UK can help with some advice on where to get test kit for others who might see this thread.

I do wish you the best of luck though. Having algae in your vacuum hose indicates insufficient chlorine during use or maybe stored wet without a way to dry out.

Edit: I checked and TFP has a link where you can buy a Lamotte fas-DPD kit in the UK.

Pool Test Kits - Further Reading

www.troublefreepool.com

Thanks, I really appreciate the help. My pool is only temporary so will be getting taken down in a month or so. From what I have read I dont think calcium is an issue to my setup. CH was 207ppm the last time I checked but that was nearly a month ago.

The vacuum hose is almost permanently wet, including during over the winter where it is just left to its own devices outside. I am just going to replace the hose I think. I think it is probably more likely the hose has never been in contact with the chlorine for long enough to kill anything in there totally. More so that than not enough chlorine in the pool. I honestly thought this was going to be a more common issue and someone would suggest a way of storing your hoses so that they dont harbour anything between uses.

I understand peoples scepticism about test results. I cant vouch for pool store testing or other photometers but I do know mine are accurate. A large part of inaccuracy is user error. I religiously maintain my cuvettes. I dont handle them because bodily oils and finger prints can affect the results. I know how not to use it because I have used it for years testing for ammonia and nitrates in pond water when I kept koi. I have never once asked for advice about my test results. I understand nobody wants to give advice based on errant test results but its on me at the end of the day. You cant just disregard other test methods out there without knowing anything about them or how they are conducted.

 

[Bperry]

Thanks, I really appreciate the help. My pool is only temporary so will be getting taken down in a month or so. From what I have read I dont think calcium is an issue to my setup. CH was 207ppm the last time I checked but that was nearly a month ago.

The vacuum hose is almost permanently wet, including during over the winter where it is just left to its own devices outside. I am just going to replace the hose I think. I think it is probably more likely the hose has never been in contact with the chlorine for long enough to kill anything in there totally. More so that than not enough chlorine in the pool. I honestly thought this was going to be a more common issue and someone would suggest a way of storing your hoses so that they dont harbour anything between uses.

I understand peoples scepticism about test results. I cant vouch for pool store testing or other photometers but I do know mine are accurate. A large part of inaccuracy is user error. I religiously maintain my cuvettes. I dont handle them because bodily oils and finger prints can affect the results. I know how not to use it because I have used it for years testing for ammonia and nitrates in pond water when I kept koi. I have never once asked for advice about my test results. I understand nobody wants to give advice based on errant test results but its on me at the end of the day. You cant just disregard other test methods out there without knowing anything about them or how they are conducted.

My hose sits outside as well, anything that’s inside just gets sucked into the filter and so I’ve never noticed anything coming out of it, and can’t recall anyone in TFP having that issue, but I haven’t been around that long. I probably should dry mine a bit more carefully in the future.

 

[incredible-bulk]

I just looked at the link you posted previously re: the Lamotte test kit. They are no longer available in the EU or the UK by the looks of it.