Little specs of algae.. mustard?

[Stressed_era]

Starting last year I had small specs that look like dirt that get caught on creases in the floor of my vinyl liner of my 18' round above ground pool. Last year I thought it was just dirt or something. It wasn't until later in the season when I got green algae bloom that I found out my stabilizer was super high and not allowing the chlorine to work properly. At that point I used an algaecide and noticed that the specs on the liner also disappeared. That's when I realized it was algea.

Fast forward to this season I drained my pool and refilled and now my stabilizer is at 42. I cleaned my de filter fingers with muriatic acid at the beginning of the season, and I've been using the BBB method. Everything's been great until today I noticed those little specs of what I assume is mustard algea. I've been maintaining 6ppm of FC, And always less than .5ppm combined. The water is crystal clear and balanced. I've never seen the FC below 3.5 and usually will add more than needed to bump my FC over the recommended 6ppm.

This leads me to believe the problem is high phosphates which are way high. We have high phosphorus in our water on long island.

Would you guys recommend using a phosphate remover or would I be ok shocking once a week? I haven't shocked since I opened it about 4 weeks ago. I've used a phosphate remover once before and it's a pain in the Rear, so if I don't have to I would rather avoid it.

 

[Cwiggs]

Welcome to TFP!

* How do you test your water? If it's the pool store, we don't really know if any of those numbers are accurate.
* In general you don't need to worry about phosphates, read more in the wiki.
* If you update your signature with your pool info it will help us help you.

If you don't have a good test kit I would get one and then do a Overnight Chlorine Loss Test to see if you have algae, if you do start a SLAM Process, including the mustard gas portion.

 

[Stressed_era]

Thanks, I have the Taylor 2006c test kit. I lost 1.5ppm overnight. I didn't start the slam process properly, no time to vacuum but there's really not much in the pool, Few small debris. I just added more liquid chlorine back up to shock level. And will run the pump.

Pool store test had phosphate over 1900ppm

 

[Katodude]

Once you see algae there is no such thing as a little algae. Think Iceberg. You can only see a little bit of it. You will need to SLAM.

 

[Rich807]

Phosphates are basically of no concern here at TFP. Pool stores love to focus on them as they can sell you more stuff, stuff you don’t need to buy & put in your pool. The TFP method has you keep your pool fixed by always running the correct amount of sanitizer (chlorine).

Pool store water testing is an unreliable joke at best. Use / rely your own kit for chemistry analysis.

Keep at it! Follow the SLAM process & the other management direction as listed in TFP pool school etc & you’ll come out the other side with a great pool.

 

[Stressed_era]

Thanks, I'm just not sure how it happened. I've been testing everyday. It was very hot this week and my pool is full sun all day, so the FC did drop to arround 3.5ppm one day. Recommended FC for my pool is 6ppm. Cya is around 45. I think I'm going to start keeping it at 8ppm.

 

[Cwiggs]

Thanks, I'm just not sure how it happened. I've been testing everyday. It was very hot this week and my pool is full sun all day, so the FC did drop to arround 3.5ppm one day. Recommended FC for my pool is 6ppm. Cya is around 45. I think I'm going to start keeping it at 8ppm.

You always round up with the CYA, so 45 should be treated as 50. At 50 CYA the min is 4ppm, so if you tested and it was 3.5ppm, that is where algae will start to grow. The target for 50 CYA is 6-8ppm. Here is the thing about the target; you want your pool to be at target pretty much all the time. So lets say your pool starts the day at 8, but you loose 5ppm to the sun, swimmers, etc. Now your FC is at 3ppm, and algae is going to grow. My recommendation is to keep the FC on the high side, and make sure your FC is near the target at all times.

Another thing I've noticed when watching others on here do a SLAM: Make sure you keep the FC above SLAM level during the entire SLAM. A lot of people relax and let the FC drop a few ppm below SLAM, the more you do that, the longer the SLAM is going to take.

Good luck!

 

[Stressed_era]

Thanks, I guess there was a few things I didn't fully understand, and I didn't think algea would start to grow that quickly at 3-3.5 ppm. Just gotta keep the chlorine a little higher, thanks for the tips..

 

[Stressed_era]

Only thing is I've been going off the pool store test for cya. But I suspect that it's lower than their reading. I don't really like the cya test, it's hard to get a good reading IMO. I feel like I can always see the dot if I try. So I'm going to treat the pool as if the cya is 50ppm. That way even if it's lower than that I'll have enough more than enough chlorine. I wish there was a better way to test cya.

 

[Cwiggs]

The cya test is difficult. You can read more info that might help on the wiki. There are pics there of what it should look like.

What I do is put the solution in the viewing tube to a certain level, say 60ppm. Then I stand up, hold it at my waist and look into the tube, then quickly look away and back again. If I can see the dot still I out in more solution to get to 50ppm. Rinse and repeat down to 40, 30, etc. Hope that helps.

 

[Stressed_era]

Thanks you've been very helpful. I'm actually starting to think I maybe just have pollen that's settled to the bottom and not algea at all based on stove other threads I've seen on here. I really need to spend some more time on here looking around.

It's collecting along creases and winkles in the liner mostly. Nothing on the walls and there is no shady part of the pool, it's all sun all day. Only shady part is behind the ladder and there's nothing there. I did open the pool earlier this year and there was a lot of pollen in it for a couple of weeks.

 

[Cwiggs]

Thanks you've been very helpful.

Glad I could help

I'm actually starting to think I maybe just have pollen that's settled to the bottom and not algea at all

That matches up with what the wiki says is common too. Regardless you have to SLAM so maybe bring the FC up after the SLAM to rule out mustard algae. Then if after you SLAM you still see the yellow stuff in the pool you'll know it's not mustard algae

 

[Stressed_era]

How many hours counts as an overnight test?

 

[Cwiggs]

I'm not sure it's hours really, it's just when the sun goes down vs comes up. The idea is that when there is no sun hitting your pool you shouldn't loose any FC. Therefore if you do loose FC when the sun is not hitting your pool something in the pool is using the FC.

 

[Stressed_era]

I'm not sure it's hours really, it's just when the sun goes down vs comes up. The idea is that when there is no sun hitting your pool you shouldn't loose any FC. Therefore if you do loose FC when the sun is not hitting your pool something in the pool is using the FC.

I'm going on day 5 of SLAM and still lost 1.5ppm over night. (20ppm - 18.5ppm) Tested at 11.30pm and this morning at 7am. Should I test earlier like before the sun comes up? (Sun was partially cloudy and low in the sky but I don't have any trees blocking it. I wouldn't consider that direct sunlight but maybe I'm wrong.)

 

[Cwiggs]

I'm going on day 5 of SLAM and still lost 1.5ppm over night. (20ppm - 18.5ppm) Tested at 11.30pm and this morning at 7am. Should I test earlier like before the sun comes up? (Sun was partially cloudy and low in the sky but I don't have any trees blocking it. I wouldn't consider that direct sunlight but maybe I'm wrong.)

Was any sunlight hitting the pool?

I'd be on the safe side and SLAM for 1 more day, do an OCLT tomorrow morning (maybe get up a bit early to make sure no FC lose to UV). If you pass the OCLT, pool water looks good and CC is below 0.5 then you are done with the SLAM! I'd hate for you to end the SLAM early and then have to just do another SLAM down the road.

 

[Stressed_era]

Was any sunlight hitting the pool?

I'd be on the safe side and SLAM for 1 more day, do an OCLT tomorrow morning (maybe get up a bit early to make sure no FC lose to UV). If you pass the OCLT, pool water looks good and CC is below 0.5 then you are done with the SLAM! I'd hate for you to end the SLAM early and then have to just do another SLAM down the road.

Yea I'm doing another day, added chlorine 2x already, gonna do one more before work and then again after work. Then I guess I have to bring it up to mustard algea shock level for one day.

 

[Stressed_era]

Passed OCLT finally. Just .5ppm FC loss, CC at zero.

I need to add water, had a lot of evaporation this week. Haven't had much rain. Had to take the weir door off last night, was laying too flat causing air bubbles to get in the pump.

 

[Stressed_era]

So I wanted to update, pools been clean, water is clear, keeping my FC on the upper end of my target FC LEVEL (pool math says 4-8) and it hasn't dropped lower than 5.5 since the slam. Lose about 2.5-3ppm over the course of a hot sunny day in full sun.

I still get very small specks on the liner in creases and wrinkles but I'm starting to think it has to be debris and dead algea. Yesterday rained all day and I only had a FC loss of 1ppm in 24 hours. CC always 0, no color change.