Cloudy water after iron removal?

[Nlambert]

After removing the iron from my pool, the pool turned crystal clear. It was amazing!

This past Sunday (6 days later) I hooked my slide up to the return jet below it (first time this season).

Prior to hooking it up, my test results were:

FC: 8ppm
TA: 50
CYA: 30
pH: 7.0 (still low from the iron removal)

I came out on Monday and the water had a slight haze to it (slightly milky looking). It almost appeared that aeration caused the water to cloud up. Below are the results after testing:

FC: 6ppm
TA: 70
CYA: 30
pH: 8+ (went past my scale)

I added some Clorox granulated stabilizer (4lbs) to bring up the CYA via the sock method and by Tuesday all of the granules were gone. FC was at 4ppm on Tuesday, so i added 1 gallon of 10% LC.

Assuming that the high pH caused the cloudiness, last night I added 1/4 gallon of muriatic acid to bring the pH back down.

This morning's test results:
FC: 4ppm
TA: 60
CYA: 50
pH: 7.4
CH: 0 (didn't register any calcium)

I can barely see the bottom of the pool at this point. I backwashed my filter to be safe and am letting it run for the day to see if it clears up. If it does not, what could cause this? Would I need to SLAM again for some reason? We were thrilled to have such a vibrant looking pool for a few days. Very disappointing to seem to be going in the other direction.

 

[Texas Splash]

I'm wondering if you had some algae in the plumbing to the slide and it just washed in on Sunday evening? To help diagnosis your situation, I would encourage you to do an Overnight Chlorine Loss Test starting this evening. Today, I would increase the FC to around 6-7 just in case it's struggling to try and avoid a potential SLAM. Tomorrow morning see how your OCLT did.

 

[Nlambert]

I'm wondering if you had some algae in the plumbing to the slide and it just washed in on Sunday evening? To help diagnosis your situation, I would encourage you to do an Overnight Chlorine Loss Test starting this evening. Today, I would increase the FC to around 6-7 just in case it's struggling to try and avoid a potential SLAM. Tomorrow morning see how your OCLT did.

That's the plan for now. We have to go find some more LC, but we plan to do that after work and then get it in the pool. I didnt think about the line having algae in it, but it's completely possible.

 

[Nlambert]

So..... as an update. I was able to pick up more LC. Brought the level to 10ppm about 4pm on Saturday. The water was clearing, but had turned from a milky color to a slight hazy green in the deep end. OCLT yesterday at 9am was 8 ppm. I added 1 more gallon of 10% LC this morning. The pool has cleared back up, but the steps and plastic pieces in the water have began to have a yellow tinge to them. I don't see any brown staining on the liner, but it isn't as bright as it was right after removing the iron.

I can wipe the steps with my fingers and some of the yellow will come off (wasn't the case with the iron before) but it doesn't scrub off with the brush. Very odd. I put a Vitamin C tablet on them and it wipes right off. I backwashed the filter late yesterday evening and it was pretty green, so there was definitely algae in the pool. Right now I am holding the Chlorine levels slightly higher than normal to hopefully help burn off any remaining algae that might be in the pool.

Current test results as of 1 hr ago:

FC: 10
TA: 80
pH: 7.6
CYA: 50

Should I continue to hold the Chlorine levels slightly high and give it more time to clear out, or could this be the iron returning? I talked to Robelle's again this morning and was told to let a pool store test the water. My iron test strips didn't register iron in the water for now.

They don't think the iron is returning and continued to say that once their sequestrant is filtered out, iron won't be in the water and there is no need to re-apply unless we add new water.

 

[Texas Splash]

One thing for sure, you can't combine TFP methodology and local pool store advice. Pool stores use antiquated industry standards coupled with some bad advice as noted above. Here are some things I can tell you for sure:
- You have iron in the water. No doubt about it. Sequestrant will contain it in solution form, but it won't help it get filtered out.
- If you have algae, the algae issue must always be addressed first via the SLAM Process before treating for metals. Of course the issue there is that increasing the FC to SLAM level will most certainly make water changes and staining worse. But you appear to have passed an OCLT which is good.
- You seem to be on a thin line right now between the iron content in the water and how high you can increase the FC (and pH).

So what now? I would keep the FC in that 5-6 range, no lower than 4 ppm. In addition, lower the pH slightly to 7.4-7.5. Let's see if that helps calm the iron changes and if you managed to avoid an algae problem.

 

[Nlambert]

No worries on the pool store testing. I have no intentions of doing that.

The yellow on the steps appears to be a little less noticeable but it is definitely staining. We can't wipe it off any longer, but a Vitamin C tablet takes it right off. We can also remove it with a magic eraser, so that's the path we will take right now. Since it's very light staining, I'm not going to concern myself with trying to remove any more iron this summer unless it gets really bad. Maybe towards the end of the season I'll approach it again.

I'll give the pH lowering a shot this afternoon and let the FC drift back down to the 5-6 range and maintain for a while. I'll post back in a few weeks to see if everything kind of levels out. I appreciate all the advice!