Please help with water color.

This is my first above ground pool opening after winter. We had it uncovered, no trees, no leaves. I've followed the process of SLAMing the pool the past 2 days. I live in south Louisiana. We don't have much winters.

My readings so far: CYA 70 (draining the water to bring to 30 -40ppm as recommended. )
pH: keeping at 7.2 with MA
With my current CYA level, I'm keeping chlorine levels according to the SLAM and chlorine/cya chart. The water went from a swamp to a light green color in a day yesterday, but within an hour this afternoon it went to a dark brown.

Please help. I have checked the FC levels every 90 minutes, I have been diligent with my numbers. Someone please help. I dont want to think of draining this pool.

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
Hello Lori and welcome to TFP! :wave: A few things:
- Increasing your FC level and watching the pool turn brown indicates iron in the water. Common for your area. Are you on a well?
- CYA adjusting okay, but don't bother pouring chemicals in at the moment if you are in the process draining. Exchange the water you need to adjust CYA, then begin the adjusting process.
- When you do begin to refill, focus on keeping the pH at about 7.2. Low is good with iron water and for a SLAM.

It sounds as if you're trying to do the right thing, but an elevated CYA and iron may be your foes - for now. We'll help. Also, please try to update your signature with your pool info, and let us know how you area testing the water (TF-100 or Taylor K-2006)? It will help us a bunch. So glad you found us at TFP. Keep us posted.
Apr 15, 2017
Lake Charles, La
Thank you for responding Pat!! I've enjoyed this forum thoroughly and it has been our go-to since we bought the pool last summer. This is my 1st post only bc I have always found my answers thru searching other threads.

We are on well water so I'm sure there is iron. I did update my signature as to our equipment and I do use the Taylor K 2006 test kit. We dropped the water level down to get our CYA level at a decent number (my fault for raising it all at once, I didn't follow the recommendations here I'm impatient). When we dropped the water hoses in to refill, that's when we walked back out to the color change. I should have taken a photo...hindsight. This morning when I checked it, it's back to green. If it were iron, would it have changed back from brown to green overnight? Is there anyway I can check for iron?

Also, I've still been checking my numbers every 90 minutes....CYA is at 40 but my FC has not changed throughout the day and I didn't lose any overnight. Does that mean I'm doing something right? lol

The thought of draining this pool just isn't in my cards. I want to see this process thru so I can compare the cost of opening it vs. keeping it running thru the winter.

Thank you for helping, have a wonderful Easter. I can also post a picture of the pool if that would help. I should have yesterday.

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
A pic would probably help. Funny thing about iron is it can react and change based on the various content of the water (i.e. pH, FC, and of course iron). There are test kits for iron, but usually they are expensive and only confirm what we already learned from trial and error. Iron can vary between green, brown, and even a shade or two in between. Since your pool was in the middle of a SLAM to begin with, draining probably lowered some of those properties, keeping the iron from reacting so abruptly.

Good thing now is that with a CYA of 40, your SLAM FC level is only 16. It still may cause the iron to react, but once there is algae, you must complete the SLAM first. You have to get rid of algae then address any staining or color changes. This statement is encouraging:
CYA is at 40 but my FC has not changed throughout the day and I didn't lose any overnight.
What I would suggest for now is simply maintain and monitor for the rest of the day and perform an overnight (OCLT) FC test this evening. If you pass the OCLT, we'll discuss the color of your water and what your CC level is.

You may still need to run the SLAM a bit longer, or you may have tackled the algae and simply need to let the FC fall down to prevent the iron from reacting any further. We'll watch for any pic and test updates and go from there. Have a wonderful Easter as well. :)
Apr 25, 2017
Covington, la
I also live in south Louisiana and I have well water. We have had our pool for ten years and we also don't winterize it bc it's not necessary here. I have always had a problem with iron and I spent countless hours and dollars on metal free, metal out, metal control, then clarifying agents and ultimately flock. Every time I added a lot of water it would turn green brown when I shocked it. About 4 years ago I tried ferritabs. I don't know how they work or why but it's the only thing that seemed to remove the iron from the water permanently. This year we drained the pool and refilled it and like an idiot I tried to go the pool store route again and used the metal out route. It worked for about a week and then when I shocked the pool it turned green brown. I ordered ferritabs again and it took about two days but my water is blue again. I hope your water is clear by this point but is not its worth a try.