newbie with water mold

Aug 11, 2012
44
Hi-

This is my first post! I have been learning a lot from you all in the past few weeks. I do have a TF-100 kit. It is great! I started the shock process a few days ago because I have had water mold. It has come and gone over past two years. Pool info:

new pool end of 2010 so only 2nd summer and pool gets full sun all day
Vinyl liner
23,500 gal
automatic cover
sand filter

The pool has been hazy for weeks now-looking better since starting the process. I believe the problem was high CYA because of chlorinator and was not told about the relationship between CYA and Chlorine! surprise! so just told to constantly shock, but never enough.

I have CYA down to i think 70-80. so shocking to 28 and checking every 90 minutes or so.
pool is pretty clear-i can see the pattern on the floor of deep end.

concern is this water mold. I no longer see but know it is lurking! it was really bad at open this season-sheets of it! lots of water replacement!

Any info on this is great!
Thanks
 
Thanks for the info!

I will keep it up! I did realize I am already really low on R-0871 after two days given I am checking every 90 minutes to 2 hours and using 40-50 drops each time! any suggestions there?

Can I bring down my CYA during this process? or would it mess things up dumping and replacing water?

Thanks
 
The only way to lower CYA is through partial drain and refill. You are still pretty high, so that would not be a bad idea.

Doing so will not "mess up" the shock process, it may slow it down as you likely have to wait while you drain and refill to start adding chlorine again.

If you are getting low on reagents, order replacements now so you will have them before you run out. You can buy refills at the same place you bought your kit ... the XL option might have been a good idea if you knew you were going to be fighting this, but hindsight ...
 
Hi-

Thanks! I did drain about 6" yesterday. Going just below the skimmer and then refilled and checked CYA this morning. I am pretty discussed because I measured from 75-100 but mostly 80! Obviously, I was wrong in my measuring before! Not very good at that test.

Seems I need to drop more water today. Pool does look good. My son got some of stuff off the bottom-very little. But there were a few globs of grey stuff. Assuming the shock process was gathering the "yuck"!

Thoughts?
Thanks
 
Someone in another thread used 5ml pool water with 5ml distilled water and that ends up giving you a 1ppm accuracy using half the drops of a normal test. That should be sufficient for checking the shock level as long as you switch back to regular testing when you do you OCLT once you think you are ready for that. BTW, I'm not sure you need the 5ml of distilled water but 10 ml seems like the smallest amount I can stir and read so I would probably do that.
 
Hi-

So the past two days I have drained total of roughly 12".

These are my numbers
FC-0
CC-1
PH-7.4
CH-280ish
TA-350 wow! have the returns turned up to bubble surface. I did do the test 2x second with the 10ml
CYA-70
So started shock process again. pool is clear. did see a bit of water mold when opened this morning but was at FC-0 so not surprised.

Just added chlorine to up to 20. The chart shows 28 and also 20 on pool calculator?

Thanks
 
poolgirl10 said:
These are my numbers
FC-0 :cry:
CC-1 :(
PH-7.4 :cool:
CH-280ish :?:
TA-350 wow! have the returns turned up to bubble surface. I did do the test 2x second with the 10ml :?:
CYA-70 :?:
So started shock process again. pool is clear. did see a bit of water mold when opened this morning but was at FC-0 so not surprised.

FC is too low; but you have the right idea. Crank it up. Why did you stop shocking before - I know you were draining - is that why?

CH - Is this a problem, do you have a CSI index that's worrying you?

TA - As above; I assume you are aerating to raise pH so you can lower it with acid and reduce TA over time based on your info above. If so you're on the right track.

CYA - What's your goal state? I don't see anything that indicates a Salt Water Chlorine Generator. If not then are you going to try to lower it further eventually? 70 is a tough place to be when you need to shock.

poolgirl10 said:
Just added chlorine to up to 20. The chart shows 28 and also 20 on pool calculator?

I think if I recall correctly that Poolcalculator.com is a little less aggressive with higher CYA numbers than the chart. Both work for run of the mill problems. The chart value is likely to get the job done quicker and with the mold is more likely to work overall.
 
Hi-
I did stop shocking while draining so why it went to 0

CSI says .52 on pool cal

CYA hoping to continue to bring down. I get full sun all day so not sure where to get it to?

No SWG

Just did the TA for first time this morning so have not done anything about it yet. Wasnt sure if it was high because of just adding water? Aerating to try and help then thought when shock process done go with
MA

Thanks! How am I doing?
 
poolgirl10 said:
I did stop shocking while draining so why it went to 0

OK - getting back to it will help.

poolgirl10 said:
CSI says .52 on pool cal

I'm not an expert but I think I understand that TA, CH, pH and Temp all play a role here. pH is one that you have the most immediate control over. If I recall a lower pH is better for CSI - but you're fighting to lower TA so you have to play a tight rope. Tinker with the pH values in poolcalculator to see what your max should be (CSI => 0.6 is where you don't want to get to). Then try to walk the tightrope of lowering it to 7.0-7.2 and raising it back up with aeration without going over your target. This will slowly bring down TA and reduce your CSI index as I understand it.

poolgirl10 said:
CYA hoping to continue to bring down. I get full sun all day so not sure where to get it to?

Lots of TFP'rs use 30-50ppm without SWG and with full sun.

poolgirl10 said:
Just did the TA for first time this morning so have not done anything about it yet. Wasnt sure if it was high because of just adding water? Aerating to try and help then thought when shock process done go with MA.

Just watch the CSI - while you have vinyl and don't have the same problems that someone with plaster might have if you get scaling - you still want to avoid it.

poolgirl10 said:
Thanks! How am I doing?

Sounds like you have a plan and you are in control. Keep up the good work!
 

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Butterfly said:
Did you wipe the bottle tip/dropper with a damp cloth between drops for the TA test?

Sometimes static can cause the drops to be smaller and the reading to be higher......so, just to be sure, here's a link to the Extended Test Kit Directions: extended-test-kit-directions-t25081.html

I'm the poster child for this tip. I thought I had a TA of 170 - it was high but not that high. Changing techniques dropped my test results from 170 to 120.
 
Hi-
I did wipe it off the second time with a paper towel or dabbed it. it did bring it down from 390 to 350! I am thinking we must have high alkalinity in the water. I remember fighting this after exchanging water at the beginning of the season. Once I am done with shock process, I will recheck and adjust with acid using the pool school advice.

We have electric cover(no fence) so shut when we are not home. It is usually open most of day. Should I be keeping shut more to not lose the chlorine? With mold I felt it needed all the sun it could get.
Just curious how others with the auto covers handle them.

Thanks
 
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