Milky Water

[NancyMyer]

This is my first posting. I apologize for its length, but I'm trying to provide all of the details. This is my first year managing a pool.

Two weeks ago, we got some metal filings in our pool and developed pinprick size metal stains on top steps. I used BioGuard erase iron stain remover and pool magnet plus. (I had used these same chemicals with great success back in January after our pool was flooded with river water and we developed some larger metal stains on the walls of the pool.)

When I purchased these products, I had the pool store test the water and was told I should be adding: 3.5 pounds of stabilizer, 19 lbs of Calcium Hardener and 116 lbs of salt. Prior to doing any of this the pool water was very slightly green but clear. At that point I was attributing the slightly off color to the excessive amount of pollen we have in the air here in the springtime. (Everything else has a green film on it at this time of year, so it seemed logical that the pool filter might be having a little trouble catching up.)

Anyway, I did the metal treatment first which required the chlorine to be low. After a few days, I added the salt, stabilizer and 15 lbs of Calcium Hardener and figured I could start slowly bringing chlorine levels back up. The pool started to get cloudy as soon as I started adding Calcium Hardener. It's now been a full week and the water is so cloudy you can just distinguish the second step. It's a blue cloudy, but very cloudy.

I hit the superchlorinate button on the SWG thinking that might fix it, but I see now from reading other posts that if I have an algae problem that will not generate a high enough chlorine level...

I have the TF-100 test kit and have performed all of the tests except the overnight chlorine test which I will do this evening.

My current readings are:

FC: 14
CH: 300 ppm
TA: 90
CYA: 80
pH: 7.2 (I have been adding acid to lower pH and TA which was at 130ppm a couple of days ago).

Any ideas?

 

[Texas Splash]

Hi Nancy and welcome to TFP. You may have two things happening. First, the Calcium increaser can at times cloud the water. If your pH was high at the time, it can enhance that as well. In many cases, time and a slightly lower pH helps to resolve that issue. Now if you had cloudiness before any of this, see any green, or think you are losing FC (Free Chlorine) too fast each day, then you may also have an algae bloom which requires a SLAM (link below).

By the way, I just noticed you have a fiberglass pool. Not sure why the need to increase CH too much, unless perhaps your equipment calls for it. Just be careful about going too high on CH. Unless the shell of that pool was manufactured with a type of calcium carbonite product, then it may not require too much calcium. You may want to check your owners manual and compare to TFP's recommended levels. My owners manual doesn't even address a CH level. If it gets too high, and you allow pH and TA to get too high, you can actually develop scale on the shell.

All of these are reasons why it's so good that you have your own test kit now and test on your own. Outstanding! So for now, I would give that calcium a couple days to see if it goes away. If you chose to do the OCLT tonight/tomorrow morning, just make sure you follow the directions on the OLCT page. If you fail that, or have any questions for us, please let us know. Great to have you with us.

- - - Updated - - -

Oh, and Nancy, your FC is very high for a SWG pool (unless you are actually doing a SLAM), so you may want to dial-back the SWG for now until you know for sure about the OCLT.

 

[tim5055]

Welcome to TFP!

My first idea is to stop going to that pool $tore. They did you no favors.

Stop trying to fix too many things at once. Right now worry about FC & pH only.

The first thing we need to figure out is if you have algae in the water. Even with the worst of the pollen, my pool has not had a green tinge to it and I'm very close. Look in Pool School and perform an Overnight Chlorine Loss Test tonight. When you do the test with a SWG, it has to be turned off during the test.

Tonight after the sun goes down please post your FC, CC & pH. Tomorrow morning test again and post the new numbers.

Keep teh pump running 24/7 until the pool clears. If you are lucky you have a reaction between the calcium you added and the pH adjustments you have been making that clouded the pool.

 

[NancyMyer]

I tested water at 8:00 last night and got the following:
pH: 7.2
FC: 12.5
CC: .5

At 7:00 this morning I got:
pH:7.5
FC:12
CC:1

 

[NancyMyer]

Since my CC level is 1 I assume from what I've read that I should SLAM the pool. If I'm understanding the charts correctly my CYA of 80 means my target shock level is 31. With a current FC of 12 I need to add 3 gallons of bleach to get to that level. I assume I should just leave SWG off until I complete SLAM. Also, is there any point in replacing some water first to try to get the CYA level down a little before I start SLAM?

 

[Texas Splash]

You are absolute correct Nancy. You've done your reading. :study: As for replacing water, you're on the high end of the scale for a SWG (70-80), but still fine. If you suspected your CYA was much higher, then you may have good cause to consider water exchange, but for now I think you are okay. If you have any questions for us as you go, please let us know. Have a nice day.

 

[NancyMyer]

Thanks so much for your previous help. It took almost a full week, but I now have a beautiful, crystal clear pool that has passed the overnight test!

I checked all my numbers this morning and got the following:

pH: 7.5
FC: 20 ( on its way down from the 31 I was using to slam it)
CC: 0
CH: 275
TA: 90
CYA: 50
Salt: 4400 ppm

Clearly, my salt level is high (after adding the recommended amount from the pool store I will never go to again!). Do I need to actively work on draining, refilling to lower that or can I just wait for normal evaporation/backwashing to take care of it?

Also, just want to confirm what my goal for CYA and FC should be. My SWG manual recommends CYA: 30-50 FC: 1-3. Your chart recommends CYA 70-80, FC: 4-6. Since I have some time before my FC levels get down to either of these ranges, I'm just wondering what I should aim for? I have to admit I find the relationship a little confusing..... and less always seems better to me? Should I leave CYA where it is and let FC fall to 1-3 or should I add CYA and keep FC in the 4-6 range?

Thanks for your thoughts!

 

[tim5055]

Thanks so much for your previous help. It took almost a full week, but I now have a beautiful, crystal clear pool that has passed the overnight test!

I checked all my numbers this morning and got the following:

pH: 7.5
FC: 20 ( on its way down from the 31 I was using to slam it)
CC: 0
CH: 275
TA: 90
CYA: 50
Salt: 4400 ppm

Clearly, my salt level is high (after adding the recommended amount from the pool store I will never go to again!). Do I need to actively work on draining, refilling to lower that or can I just wait for normal evaporation/backwashing to take care of it?

Also, just want to confirm what my goal for CYA and FC should be. My SWG manual recommends CYA: 30-50 FC: 1-3. Your chart recommends CYA 70-80, FC: 4-6. Since I have some time before my FC levels get down to either of these ranges, I'm just wondering what I should aim for? I have to admit I find the relationship a little confusing..... and less always seems better to me? Should I leave CYA where it is and let FC fall to 1-3 or should I add CYA and keep FC in the 4-6 range?

Thanks for your thoughts!

Evaporation will not reduce the salt level as it stays behind, only the water evaporates. If your SWCG is happy and producing chlorine I would not worry for now.

Now, our recomendation is CYA of 70 - 80 for a SWCG pool. With your 80 CYA you are good, but keep the FC no lower than 4 and target 6 to keep it above 4. Did I say 4 was your minimum?

It's funny, but the higher CYA will actually let the SWG work less.

 

[txnole]

Congrats on your success!!!

 

[pooldv]

What kind of SWG is it and what does the manual say about high salt? My Pentair SWG gives high salt warning at 4500 ppm but will continue to produce chlorine even in high salt condition. As Tim says if your SWG is making chlorine then it is probably fine, but I would check the manual to see what the manufacturer recommends.

 

[NancyMyer]

I have a Hayward Salt & Swim SWG. The manual recommends a salt level of 2700-3400 and says it might shut down at higher levels. I haven't turned it back on yet as my FC level is still at 20 (after slamming the pool). I guess I'll just see what happens when the FC lowers and I start the SWG back up. If it doesn't produce chlorine, then I drain some water and refill, right?

 

[pooldv]

Yes, that will work fine.