Another Algae or Dirt Thread

[C&HSewell]

My wife and I joined this forum during the recent build of our new pool and have been lurking for a few months now. I have read many of the threads about if it is algae or dirt, SLAM dont SLAM, but felt it was time to reach out. We have been dealing with what I think is dead algae, but the pool guy(we had hired after the build to help since I was immoble due to surgery, but have since stopped the service) said it was dust from the flagstone coping, for about 1 month now. I have tested religuosly in the AM and in the PM over the last 2 weeks because of this "stuff" on the bottom at mainly the seams in the liner, but did expand slightly the other day. It is not gritty and will dissipate when disturb. I have no FC loss overnight and the water is clear.

Here is what I have been consistently seeing with my own personal testing with the Taylor 2006C:

FC: 6.4
CC: 0
CYA: 50
TA: 80
Ph: 7.6
CH: 180

Should I SLAM as a precaution?? Please Help!!

 

[Texas Splash]

Welcome to TFP! If you performed the Overnight Chlorine Loss Test properly and passed, I see no reason at this time to go into a SLAM Process. Instead, you might be sure there is good water circulation across all areas of the pool. You should also update your signature with all of your pool and equipment details. Include your test kit as well. That info might prompt more thoughts.

Pool Care Basics

 

[C&HSewell]

Welcome to TFP! If you performed the Overnight Chlorine Loss Test properly and passed, I see no reason at this time to go into a SLAM Process. Instead, you might be sure there is good water circulation across all areas of the pool. You should also update your signature with all of your pool and equipment details. Include your test kit as well. That info might prompt more thoughts.

Pool Care Basics

Thanks, I had the details in my profile and just added to my signature.

 

[Texas Splash]

This is a new pool, so I wouldn't think there should be any issues with the filter. Do you know what type of media was initially filled? Was it sand or something else? Has it been windy in your area, or do you see anything around the pool decking that could be related to what is settling on the floor?

 

[C&HSewell]

This is a new pool, so I wouldn't think there should be any issues with the filter. Do you know what type of media was initially filled? Was it sand or something else? Has it been windy in your area, or do you see anything around the pool decking that could be related to what is settling on the floor?

It is a sand filter and we do typically have a steady gentle breeze but nothing on or around the decking, aside from the flagstone coping. I did perform another OCLT last night. Tested at 8:30 after the pump shut off and it was FC of 6.6 and then again at 6:30AM this morning, before the pump started, and it was still 6.6. But out of curosity I just retested at 8:45AM and it is now FC:5.8 CC:0.

 

[wireform]

How's the pressure on the gauge compared to a clean psi reading. Perhaps you need a thorough backwash and you may benefit from adding de to the sand filter

 

[C&HSewell]

How's the pressure on the gauge compared to a clean psi reading. Perhaps you need a thorough backwash and you may benefit from adding de to the sand filter

PSI looks normal, a clean pressure is 10 psi.

 

[PoolStored]

Tested at 8:30 after the pump shut off and it was FC of 6.6 and then again at 6:30AM this morning, before the pump started

From the OCLT Instructions:
If performing the OCLT independently as a diagnostic test, it is vital the pump be running at least 30 minutes before the grabbing the nighttime and morning water samples for testing in order to ensure the water is properly mixed.

 

[C&HSewell]

From the OCLT Instructions:
If performing the OCLT independently as a diagnostic test, it is vital the pump be running at least 30 minutes before the grabbing the nighttime and morning water samples for testing in order to ensure the water is properly mixed.

Ahhh!! So I need to grab the evening sample before the pump shuts off and the morning sample 30 mins after the pump starts. Which would explain why it did infact drop .8. Would that possible indicate algae?

 

[PoolStored]

Ahhh!! So I need to grab the evening sample before the pump shuts off and the morning sample 30 mins after the pump starts. Which would explain why it did infact drop .8. Would that possible indicate algae?

Yes, but the you need to collect after sunset and before sunrise. You may need to adjust your pump schedule to run before/into sunset and before sunrise.

Just do the test again. When someone has a 1ppm OCLT, it is close and I'd tell them to SLAM another day. Not sure on your testing procedure. Do you have a smart stir? Are you squeezing drops REAAAAAALY slowly and allowing them to drop on their own, or are you quickly squeezing drops? Smaller drops, from quickly squeezing will give a larger FC result.

 

[C&HSewell]

Yes, but the you need to collect after sunset and before sunrise. You may need to adjust your pump schedule to run before/into sunset and before sunrise.

Just do the test again. When someone has a 1ppm OCLT, it is close and I'd tell them to SLAM another day. Not sure on your testing procedure. Do you have a smart stir? Are you squeezing drops REAAAAAALY slowly and allowing them to drop on their own, or are you quickly squeezing drops? Smaller drops, from quickly squeezing will give a larger FC result.

Thanks, I will retest again and pay close attention to the way I drop because it is possible I was rushing the drops because I knew the count would be high.

 

[PoolStored]

Let the drops fully form and drop on their own weight.

 

[wireform]

And completely vertical

 

[C&HSewell]

Yes, but the you need to collect after sunset and before sunrise. You may need to adjust your pump schedule to run before/into sunset and before sunrise.

Just do the test again. When someone has a 1ppm OCLT, it is close and I'd tell them to SLAM another day. Not sure on your testing procedure. Do you have a smart stir? Are you squeezing drops REAAAAAALY slowly and allowing them to drop on their own, or are you quickly squeezing drops? Smaller drops, from quickly squeezing will give a larger FC result.

Performed another OCLT and was very precise with my drops and testing. Last Night was FC: 5.6 CC: 0.0 Rechecked at 6:30AM(pump had been running for over 30 mins and the sun had not risen) and it was FC: 5.2 CC: .2. While I am happy I did not lose 1PPM overnight I am confused/concerned that I wound up gaining .2PPM CC. Also, the material collecting at the seams in the liner is increasing slighly and is now also at the seams in the deep end as well. Water is still very clear, to the point I can count the number of the holes on the main drain cover if needed and can clearly see the pattern on liner or see a dime on the bottom.

Any thoughts!?!?!

 

[PoolStored]

Performed another OCLT and was very precise with my drops and testing. Last Night was FC: 5.6 CC: 0.0 Rechecked at 6:30AM(pump had been running for over 30 mins and the sun had not risen) and it was FC: 5.2 CC: .2. While I am happy I did not lose 1PPM overnight I am confused/concerned that I wound up gaining .2PPM CC. Also, the material collecting at the seams in the liner is increasing slighly and is now also at the seams in the deep end as well. Water is still very clear, to the point I can count the number of the holes on the main drain cover if needed and can clearly see the pattern on liner or see a dime on the bottom.

Any thoughts!?!?!

I'm unconcerned about the CCs. With stuff on the bottom, your water is not clear yet. Keep on Slamming!

 

[C&HSewell]

I'm unconcerned about the CCs. With stuff on the bottom, your water is not clear yet. Keep on Slamming!

Thanks.. I had not started the SLAM process since I was not sure if it was "dust" or algae. One quick quesiton regarding the correct SLAM level to achieve. Do I go up to and hold at the Yel/MstrdShock level of just to the Shock FC Level that is referenced on Chemgeek's chart?

 

[PoolStored]

Thanks.. I had not started the SLAM process since I was not sure if it was "dust" or algae. One quick quesiton regarding the correct SLAM level to achieve. Do I go up to and hold at the Yel/MstrdShock level of just to the Shock FC Level that is referenced on Chemgeek's chart?

The easy way to tell is to feel it, if it's gritty it's sand, if it 'slimy', slippery, it's algae. Are you able to grab or collect some and wipe on a papertowel, and let it dry. If it's gritty, it's sand/coping material. If not...algae.

 

[wireform]

I see no reason to assume mustard algae just do the simple slam, keep the FC at slam level as much as possible. Keep brushing and stirring up that stuff in the seams you speak of so it gets into the water stream and get caught in the filter. Since you have a sand filter add some DE in to raise it by "1" psi to catch the finer stuff. Be on the lookout for the pressure to rise faster and backwash when it reaches 25% increase from clean pressure.

 

[C&HSewell]

The easy way to tell is to feel it, if it's gritty it's sand, if it 'slimy', slippery, it's algae. Are you able to grab or collect some and wipe on a papertowel, and let it dry. If it's gritty, it's sand/coping material. If not...algae.

I tried to collect some of the material with a paper towel and it just disappered into the water and there was no grit. Based on this, I beleive it is safe to say it is alage. So in order to make sure I start and do the SLAM correctly, to what level do I need to get the FC to? Just to the 20 PPM on the SLAM Chart or to the 29 on Chemgeeks chart for Mustard Algae? Also, I need to keep it there until the water is clear, with no "stuff" at the seams, and that I do not lose more than 1PPM of FC from the FC SLAM level, and no CC above .5? Just trying to fully understand the level and how long to keep it there.

 

[PoolStored]

I tried to collect some of the material with a paper towel and it just disappered into the water and there was no grit. Based on this, I beleive it is safe to say it is alage. So in order to make sure I start and do the SLAM correctly, to what level do I need to get the FC to? Just to the 20 PPM on the SLAM Chart or to the 29 on Chemgeeks chart for Mustard Algae? Also, I need to keep it there until the water is clear, with no "stuff" at the seams, and that I do not lose more than 1PPM of FC from the FC SLAM level, and no CC above .5? Just trying to fully understand the level and how long to keep it there.

Just to the SLAM level. Your FC SLAM level is 20. You got this.

Yes, keep it there until the water is clear, with no "stuff" at the seams, and that I do not lose more than 1PPM of FC from the FC SLAM level, and no CC above .5. Test, replace FC with Liquid Chlorine to get to target level. For SLAM the 10mL FAS-DPD test (.5ppm) is plenty accurate and will save reagent.