If you tested FC after dusk last night (30 mins after last adds), did not run your SWG overnight, left your filter on and tested FC this morning before sunrise then you have 1 CC which means SLAM. You are not supposed to lose any FC overnight because there is no UV or heat to affect it. Only organics can use FC at night. PS: you've been on here for a while now, it's time to fill out your signature so we can see what all the details of your pool and equipment are including test kit.

You didn't check CC - or at least log it. Is it .5 or less? That is one of the criteria, where all 3 need to be true.

The picture strongly suggests it is dead algae settling out. Your low level of FC last week bit you. A sand filter (even with glass media) can be less effective at getting the dead suspended stuff out, especially with a robot stirring some back into suspension. It will get it, but perhaps more slowly. If the amount does not greatly lessen over the next couple of days, you still have actively growing algae.

The criteria:
CC of .5 or less
FC overnight drop of 1 or less.
Crystal Clear and no sign of visible algae - alive or dead.

Thanks Newdude. I put 8 lbs of stabilizer in yesterday and that brought my CYA up to 30. The rest of my readings are below. When my pool was last sparkling clear, my TA was running 140-160.....last year it ran a little above 200 and was never sparkling.

todays test
FC - 22 (I know this is too high...too much chlorine got put in last night on accident)
CC - .5
TA - 340
CH - 275
PH - 7.5
CYA - 30

I dont know what is causing me to have such high TA?

Skimis said:

Two days ago I opened the pool

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Skimis said:

Am I just too impatient?

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Yes.

A pool that particular shade of green is going to take time. You can see considerable progress between picture 1 and 2, but it's still got a long way to go.

Are you sure the pressure gauge on your filter is good? It's odd for a DE filter to not need cleaned often with that kind of water, if it is working properly.

mblind said:

I have not sought out the advice from a pool store

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You got industry advice one way or the other. We call it pool store advice as that where most people get it, but whether it was a neighbors pep talk, books, online reading, etc, the industry advice puts way too much focus on Ph, TA and CH while blowing off the chlorine part which is the critical one for being sanitary.

mblind said:

Since CYA doesn't rise without adding it, and since I am draining a bit at a time, shouldn't my CYA go down too?

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You got it. But multiple drains also removes good water, so it gets less efficient each round. Let's use 50% for simple math, the first round removes 50% of the original water, then 25%, then 12.5%, then 6.25%. You drained 200% of the pool volume to get to 93.75%.

The #s are more favorable with smaller drains such as 10%, but the decimals are longer and i wasn't feeling more math this morning. Its still early. Anywho, just getting the theory across, multiple drains will get you there just not as quick as many think.

Chems:

Salt 3200
TA 90
CH 350
PH 7.6
FC 4
CYA 60

thetekgeek said:

Honestly - it looks a bit like dead algae to me.

Perform an OCLT - Perform the Overnight FC Loss Test (OCLT)

If you pass, great. IF you fail - SLAM - SLAM - Shock Level and Maintain

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Performed the OCLT as you recommended. FC last night was 7 and 6 this morning. So I'm assuming it must be dirt.

Okay - overnight test results:

10 pm - 8.4
6 am - 5.8

This means algae, right?

In addition to the above, get the free PoolMath app for your phone. You enter your readings from your new test kit, and it does the work to tell you how much of what to add.
If you elect, you can pay the $8/yr charge to have it log all your past entries, so you can see how things are trending. That brings the bonus that if you use the same username for it, you can link to here - and we can see your history also. No typing or screenshots for you to do when posting, and easy for us to see what is going on.

Pools only go green due to not enough, or not consistently enough, chlorine (CL). CL gets used up by the sun, so has to be replenished very often. Not having enough may be due to scheduling issues - time to test and add on a very regular basis. Or it may be due to the products used. Chlorine Tablets are the big item here. They contain stabilizer (CYA) and are constantly adding it, along with CL. An appropriate amount of CYA is beneficial. Tabs are great as far as the schedule - one only needs to check periodically. But the CYA they add never goes away, and builds up. Most pool places never recognize that with more CYA in a pool, the greater amount of CL that needs to be added to keep the pool sanitary. They refer to "chlorine lock" or other terms, that is fiction, and advise a one time "shock" of a massive dose. Sometimes with products that appear to work, but add their own bad things (think bagged non-chlorine shocks). The "shock" may temporarily make the pool look better, as it kills some (but never all) of the algae present. The underlying problem is still there, and more CYA means needing more tablets - until the levels are impossible to maintain correctly. So the algae comes roaring back.

Here, we advocate dosing CL based on your specific CYA level, using products that do not add extra CYA. That means constant testing and adding. Likely daily or every other day. Or buying a device (Salt Water Chlorine Generator - SWCG) that will make and add CL consistently by itself, all the time. To defeat a green pool, we elevate the CL level for an extended time - days, or even weeks (for really, really bad cases), to ensure that ALL algae is killed.

Tabs have a place, and if schedules make it such that the frequent monitoring is impossible to do (and a SWCG is not a current option), then one has to accept the fact that there will have to be times where the pool has to be at least partially drained, to get rid of the high CYA level, and filled with fresh water.

mblind said:

and went back to a granular chlorine so I would not be adding to the level of CYA.

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granular chlorine (dichlor) also contains CYA. Was it calhypo or dichlor?

Newdude said:

They are about the same accuracy, which is not very. Ans both are vague comparison tests without an actual value.

You need a fas/dpd test for actual, and reliable FC values.

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Thanks! I guess I should have purchased the K-2006 kit rather than the K-2005. As a person who is just starting on this journey, I did not know what the difference was. All I saw was one was about $10 cheaper.

Newdude said:

Sounds poolstore-y. Worry about the long term things while the short term thing swamps you. (High CYA and low FC)

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Well, to be truthful, I have not sought out the advice from a pool store. The only thing I have done with a pool store is had them open and close the pool last year since I did not know what I was doing. I watched and learned and did my own opening this year. I know my CYA is high. I was hoping that I could address this in a slightly different way which does involve draining as that is the only way to decrease CYA. Read on.

Newdude said:

You'll need to drain to lower the CYA and refilling will throw off your TA/Ph. Abandon that for now.

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Unfortunately, I am unable to drain the pool down the whole 4000+ gallons it will take to decrease my CYA by amount that I would need. I was thinking that I could address this in stages. I was planning on draining a few hundred gallons (about 700 gallons) each time I vacuumed to waste and/or backwashed, that I could bring down the CYA a little each time. The people who owned the home prior used an auto chlorinator. When I opened last year, the person asked if I wanted it reattached. I had no idea what it was and asked his opinion. He said they have their pros but he did not recommend them. I do not use it. My thought is that the CYA would go down some each time and I would get it down to where it was needed. I did use stabilized pucks in a floater last summer. I have not used them this year and went back to a granular chlorine so I would not be adding to the level of CYA. Based on my calculations, I figured that I could have the 4000 gallons replaced in about a month. In the mean time, I wanted to adjust my TA and pH and then get my FC in line. Am I wrong on this? Since CYA doesn't rise without adding it, and since I am draining a bit at a time, shouldn't my CYA go down too?

Newdude said:

Was it stored climate controlled ? If so they're good for a long time.

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As climate controlled as possible. I keep my kit inside in a cabinet when not in use. I have ordered some replacement testing solutions just to be sure.

PoolStored said:

Light is important for turbidity tests. Not sure what video to which you are referring.

For CYA over 90, use this and start at #8:

CYA - Cyanuric Acid Test

Cyanuric acid (CYA) is the chemical name for the product commonly called “pool water stabilizer” … Read more…

www.troublefreepool.com

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Thank you this article it is immensely helpful! I’ll give this another go as I made several missteps it seems in my teast. The video I am referring to is in the TF’s you tube channel. It’s not as detailed as the instructions you shared. Any tip for accessing tpool school resources? When I’m logged in to participate in the forum it does not allow me to access articles or links that you shared. If I log out all is well and I can go through this article and all the resources. I noticed this when I registered for this site again actually.

The Stenner injector should be rebuildable. I have not done it yet so I can't confirm, but I would attempt to open it up and see if the duckbill is stuck.

--Jeff

Okay, well, I cleaned everything. Tools, toys, ladder. Scrubbed under every fold in the liner, drain cover, skimmer part. My FC hasn't dropped below 12 since I posted and my entire pool is yellow today, with the FC at 16. I'm guessing I have a circulation issue. I will post in one of the other sections.

jonpickles said:

I have a 13000 gallon semi above ground hybrid pool and it was green for most of last season and now it is bright green again. I'm getting testing done tomorrow and I'll post the results. I spend $988 last year to resolve the issue!

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Welcome! See above link for getting your own test kit. The pool store testing is just designed to sell you $988 worth of stuff that doesn’t usually work.

hhoran said:

Question remains--how could CYA <40 last November suddenly have become >100 in May, when the only chemicals added to the pool were liquid chlorine and three inch tabs for three short 5 day periods. No dichlor, trichlor or other chemicals added.

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The 3 inch tabs have CYA in them. That’s trichlor.

While were at it. I’m also tightneing other connections. How do i tightes the inlets?

Pry off the white housing?