CYA disappeared/reduced

[basod]

Had two algae outbreaks after testing Sunday CYA 30. First algae bloom Tuesday morning with FC 1.5 cc 1.5 beat it back slamming to 15fc Passed OCLT Wednesday morning only wake up Thursday with the pool coated in algae again with FC 9. Brought FC back up to 13 after vacuuming everything brushing and wiping all nooks. Pulled my main drain cover to check because it is plugged due to a leak years ago. Had a bunch of funk in it vacuumed and backwashed immediately.

Added DE to the filter yesterday afternoon to polish the remaining haze in the water added 1" of fill water to backwash and added DE again.

Passed OCLT at 12.5FC 0cc this am checked around 1300 and FC at 8.5 , 0cc - scratching my head.
gallon of 10% brought me back to 12.5fc with 0cc
checked CYA nearly to the top of the tube twice

Maybe this magical bacteria is living in my pool

 

[basod]

Should add after sun is off pool this afternoon FC holding 12.5 with no additional bleach

 

[pooldv]

It is rare but under the right circumstances with very low FC it is possible for bacteria to grow and consume your CYA.

 

[basod]

It is rare but under the right circumstances with very low FC it is possible for bacteria to grow and consume your CYA.

Understood.
Seems weird during hot summer temps during two sequential slams to see CYA disappear, granted I don't know when it disappeared from 5 days ago.
I added some CYA in a sock this afternoon and my water appeared to clear up? with no FC reduction...
Had a power outage so the pump was down for a bit upon restart the pressure dropped from 11.5 to 10 - makes no sense what so ever.
I've calibrated gauges and transmitters my whole adult life and never seen a gauge drop after water hammer(power cycle), usually they offset high never low.

Tried to shoot for 30 on my CYA see what's happening tomorrow

 

[duraleigh]

I added some CYA in a sock this afternoon and my water appeared to clear up? with no FC reduction...

Are you thinking the CYA made your water clearer?

read "The ABC's of Pool Water Chemistry" up in Pool School......you really have some basic misconceptions and need to get a solid grasp of pool water chemistry.

If you get algae, you must SLAM your pool. Have you looked at that process?

How are you testing?

As I'm sure you know there is no magical bacteria....nor is it consuming your CYA.

 

[PAGirl]

Rwmember, too, that a SLAM isn't over until all 3 criteria are met. If the water was still hazy, you should keep it at SLAM level until it's clear. Are you brushing often?

 

[basod]

Are you thinking the CYA made your water clearer?

read "The ABC's of Pool Water Chemistry" up in Pool School......you really have some basic misconceptions and need to get a solid grasp of pool water chemistry.

If you get algae, you must SLAM your pool. Have you looked at that process?

How are you testing?

As I'm sure you know there is no magical bacteria....nor is it consuming your CYA.

I don't think there is a misconception on my end and no I don't think the stabilizer cleared my water probably had more to do with lighting conditions.
Using the TF-100 test kit and have been for over a year now. Fresh reagents few weeks ago.
Read all the resources in pool school and they are very informative.
What's strange here is last weekend's test results
pH 7.4
FC 5
cc 0
ch 225
ta 80
cya 30

Using pool math to reduce CYA to below 20 say 18, I'd have to change 40% of my water.
That didn't happen obviously.
Added 38oz of stabilizer last night for a 10ppm rise doubt it's all in the water yet.
This morning test
pH unknown
FC12.5
cc 0
ch 200
TA 80-90
cya dot disappears ~after the 30 line. I say 28

 

[duraleigh]

What's strange here is last weekend's test results

I do not understand why you find those readings strange. They are irrelevant now, anyway, but I see nothing strange about them.

Secondly, what questions do you have about your test results from this morning?

What does your water look like this morning?

 

[basod]

Rwmember, too, that a SLAM isn't over until all 3 criteria are met. If the water was still hazy, you should keep it at SLAM level until it's clear. Are you brushing often?

Yes I'm staying on top of the brushing. Water is almost crystal clear.
Without enough CYA when I thought the FC was fighting algae it was actually going away from UV exposure. Passing the OCLT and then at some time during the day FC dropped enough for the algae to come back

 

[basod]

I do not understand why you find those readings strange. They are irrelevant now, anyway, but I see nothing strange about them.

Secondly, what questions do you have about your test results from this morning?


What does your water look like this morning?

Yesterday afternoon cya was almost not registering? While I had a reading of 30 five days prior doesn't seem strange?
how is that irrelevant?
Unless high FC interferes with the CYA test?
The water looks almost there.

 

[PAGirl]

Were the conditions the same for both CYA tests? (Sunny, back to sun, waist high) it can make a difference, +/- 10.

 

[kimkats]

What a ride you have been on! I THINK I can help get your water looking like a jewel. Lets act as if you have done nothing to your pool up to now okay? I just hit the "restart" button on this thread LOL.

HI! I am sorry to hear that you are having trouble with your pool. How does the water look TODAY? If you take and share a picture it would be helpful.

Testing-I have MY way of testing CYA. Lets have you try it my way okay?

CYA-mix up your regent and pool water like stated in your test kit. Let it sit for a couple of mins. Now go outside and stand with your back to the sun. Pour the mixture to the first line in your tube (100). GLANCE in the tube as it is held at your tummy. If you see the dot fill to the next line. GLANCE in again. IF you still see the dot then fill to the next line. Keep filling to each line until you cannot see the dot when you GLANCE in.

We will have you round up to the next line so why not just go line to line? Much faster and easier to me! You will notice there is no 28 or such on the tube so.......my way makes sense. Many others have found this to be very helpful and less frustrating.

Now run a full set of tests and post them here please.

You say you have just cleaned out your main drain hole and found all kinds of yuck. Have you taken the light out and cleaned behind it? What kind of steps do you have? If a ladder have you taken it out and cleaned it real good? Did you use your pool's toothbrush to clean all around the returns and skimmer box? If not please do so.

Now lets talk about the SLAM. It is a process instead of a one time thing. The M=Maintain is THE most important thing with a SLAM. As in Maintain the FC at your SLAM level for you CYA level. Here is the chart, please print it out:

Pool School - Chlorine / CYA Chart

Here is the SLAM link:

Pool School - SLAM - Shock Level And Maintain

We will know about how long you need to SLAM when I can see your water.

I am VERY hopeful we can get your pool clear enough where you can read the heads/tails of a coin on the bottom of it.

Let me know if you have ANY questions.

we got this!

Kim:cat:

 

[basod]

Hey Kim
I run my CYA test exactly like you state going to each line and viewing. When the dot disappears I pour back into mixing bottle and then fill to lower line and add small amounts until the dot disappears to get a tighter number(I know not necessary) but this way I can bounce the number against the pool store. Last time I brought a sample for metal analysis my guess was over 30 maybe 31-34 pool store tested at 32.
Understand the view tube isn't linear. Doing the test twice has brought my confidence in what I'm seeing is accurate.

As as far as the slam water looks nearly perfect FC is holding better today only dropped from 12.5fc to 12

 

[kimkats]

Your water does look good! Now do something for me..........PLEASE stop going to the pool store and testing (except for metals). They do it wrong more than they do it right AND can cause you some major problems if you listen to them. All it does it muddle things up.

YOU have a good test kit. Use it AND trust it. Use the tools here on TFP along with what your test kits show you and you will save money and aggravation.

You say in your first post of this thread that you had "two algae outbreaks". You did not have two outbreaks. You had one that you did not SLAM all of the way gone. Even though you had a OCLT that passed that is only ONE part of passing.

Have you cleaned every thing like I suggested above? It will take a toothbrush to get to the tiny spots.

I hope things keep going this way for you and your pool!

Kim:cat:

 

[basod]

Ladder doesn't go in the pool unless little ones are around and no light I have a couple directional beams mounted to the gazebo adjacent pool for night time cannonballs and prevent stepping on a snake�� More than a few of those around here.

 

[C3Cl3N3O3]

I had an unexplained loss of CYA last week you can read about in this thread. So was it bacteria? I don't know. The equivalent of four pounds of stabilizer just went poof. If this were bacteria, it took hold and converted the CYA very quickly (less than 48 hours with crystal clear water). I would expect this would have left a lot of ammonia in the pool, but there was no evidence of that. So I'm suspicious of the bacteria explanation in my case. I had a lot of complex chemical reactions going on in the pool at the time and I suspect there is a non-biological process that the TFP hasn't cracked the case on yet (although the bacteria is certainly a real phenomenon).

 

[pooldv]

There are three steps to the nitrification process. Each takes different bacteria. If all are present it will happen quickly and to ammonia will ever be present. First is conversion to ammonia, then ammonia is converted to nitrite and then nitrite is converted to nitrate. That is just science.

What isn't cracked is when, how or why some of that bacteria is or isn't present and under what conditions.

 

[C3Cl3N3O3]

I can't say it's impossible pooldv, but you are adding a whole new ammonia to nitrite cycle to this process that completed start to finish in 48 hours or less.

I suffered from CYA over 200 and poorly managed chlorine for several years and was never visited by the bacteria. Now I took my FC down for 48 hours on a well-managed pool with clear water and WHAM there they are? Hmm.

 

[pooldv]

CYA disappearing has been much more prevalent this year than in years past. All over the country. No idea why. My guess is aliens!

The nitrification process takes minutes to hours, not days. I've watched it happen thousands of times in saltwater reef tanks and koi ponds for more than 10 years.

 

[C3Cl3N3O3]

CYA disappearing has been much more prevalent this year than in years past. All over the country. No idea why. My guess is aliens!

Yeah I've seen that mentioned on the TFP. Very odd. That actually supports the bacteria hypothesis, because a non-biological explanation wouldn't vary year-to-year. We're infected!