Pool Is Green With High Chlorine Reading

[jonathan8610]

I opened my pool about a month ago and have been in the SLAM process for about 2 weeks at this point. There was a large amount of leaves that had accumulated at the bottom of the pool but I have netted almost all of them now. The water went from dark green, very cloudy and could not see the bottom at the beginning of SLAM to a medium-light green, cloudy, but can see the bottom for the most part. While it was progressing early on, I feel like I've hit a wall where I can't get the water to go from green to blue. The filter seems to operating at its regular PSI level and I backwash once it's about 25% higher than the normal reading.

After some initial tests after opening, I added baking soda to increase alkalinity to 50 and since then have been adding liquid chlorine every day to keep my chlorine at or above the SLAM level. Should I just continue to execute the process and keep at it or am I missing something?

FC - 20
CC - I did not test but since the water is cloudy I figure it is not 0
TA - 50
pH - 7.2
CYA - 40

 

[reggiehammond]

Keep on the process... your results are not abnormal. There can be a little plateau from time to time.
Are you confident on your CYA testing? If your CYA is actually 50/60, then your SLAM levels are not sufficient.

 

[JamesW]

Test for CC.

 

[jonathan8610]

Keep on the process... your results are not abnormal. There can be a little plateau from time to time.
Are you confident on your CYA testing? If your CYA is actually 50/60, then your SLAM levels are not sufficient.

I will redo the CYA test to make sure the reading was accurate.

 

[jonathan8610]

Test for CC.

OK, when I do another test to recheck the CYA, I will also test for CC. I just figured since the water was cloudy there would be some level of CC and wanted to save the reagent for when the pool seemed clear and confirming through OCLT test, but I will check that.

 

[Mdragger88]

Do you have steps or a ladder? If so remove them asap & clean them thoroughly inside & out.
Slam fc level for cya of 40 is 16ppm

 

[Mdragger88]

 

[jonathan8610]

Do you have steps or a ladder? If so remove them asap & clean them thoroughly inside & out.
Slam fc level for cya of 40 is 16ppm
View attachment 566533

No steps or ladder. Thank you, I have been referring to this chart and keeping my FC a bit higher than the chart recommendation as a bit of a buffer since I'm not able to test multiple times per day.

 

[jonathan8610]

View attachment 566535

I've started to make a more concerted effort with brushing the floor and walls of the pool and hoping this helps. Now that I can see the bottom of the pool, I have vacuumed a few times and will continue to do that as well. I've been backwashing when the filter pressure rises 25% over clean pressure and after vacuuming.

 

[Mdragger88]

Be sure to get the sample for the cya test up to room temp before performing the test to ensure accuracy.
Its been known to show falsely lower with really cold water.

 

[jonathan8610]

Be sure to get the sample for the cya test up to room temp before performing the test to ensure accuracy.
Its been known to show falsely lower with really cold water.

Interesting, I did not know that. I will let get to room temp before testing next time.

 

[Mdragger88]

Interesting, I did not know that. I will let get to room temp before testing next time.

I just fill the little squeeze bottle and put it in my pocket for a little bit- easy peasy

 

[jonathan8610]

I retested the water and it was at 1 ppm CC. I did a CYA test and after re-reading the Pool School article on CYA, I realized that if the black dot disappears at 40, to count it as a reading of 50, so that was an error on my part. So my reading should actually be 50. I was in a bit of a rush this morning and not sure the sample was fully at room temperature, but it certainly warmed up a bit. It has been very cold in the mornings here in CT, so I think I need to let the sample warm up more. I'll use my Thermapen digital thermometer to make sure the temperature is where it needs to be for my next test. Does anyone know how much temperature affects CYA readings? I suppose it's possible the CTA is actually above 50. I did add stabilizer to the water after opening because after my initial test, it looked like there was practically none in the water, but I messed up by not waiting for the water to get to room temperature to get a more accurate reading. I'll know for next time, at least.

 

[Mdragger88]

There’s an indepth discussion about it here

At what water temp is CYA test reliable?

Easy question. I'm opening this weekend to avoid any algae (porus loop-loc cover). What are the effects of cooler water on CYA test - does it read low or high? Being precipitate based I would assume it would read high as there would be more precipitate sooner. Secondly I guess if I bring the...

www.troublefreepool.com

In general if the sample is over 70 degrees you should be good
Some people have noticed a difference in results & some do not. I generally redo the test multiple times anyway to help me make a decision/average. (Pour the mix back in the squirt bottle & do it again)
You’re not aiming for perfection just making sure you’re chlorinating at a high enough fc level. It gets easier to judge as you continue doing it.

 

[jonathan8610]

I retested the water this morning and made sure the water was at room temperature prior to testing CYA. I actually did not get a different reading with this method. I performed the test 4 times and got the same result each time. The black disappeared at 40, so I believe this would mean my CYA is 50. My FC reading was 21 and was 20 the other day so it does not appear to be dipping below the SLAM level for 50 CYA. I suppose for now I'll keep at it with brushing, vacuuming, backwashing, SLAMing, etc. Anything else I could be missing?

 

[MITBeta]

Can you see the dot at 30 but not 40 or 40 but not 50?

 

[Mdragger88]

Is the water still greenish?

 

[jonathan8610]

Can you see the dot at 30 but not 40 or 40 but not 50?

I can see the dot at 50 but not 40.

 

[jonathan8610]

Is the water still greenish?

Yes, here are a few photos I took this evening. It’s been this way for about 2 weeks now. I’ll try and continue to get the remaining leaves out and continue brushing. I haven’t needed to backwash much which is interesting, so I’m not sure if it’s a water chemistry or filtration issue.

 

[Mdragger88]

Even though you can’t see you need to remove all the organic material- vacuuming & scooping blindly.
How often are you testing & replenishing fc?
Are you on a well?