AA Treatment then Partial Water Drain

aeh0603

Well-known member
Apr 6, 2016
115
San Diego, CA
#1
Hi everyone! I'm getting ready to do an Ascorbic Acid treatment for metal staining. I also need to do two 50% water draining cycles to get my CYA and CH levels in a better range. Since the AA Treatment simply pulls the metal stains back into solution I figured I would do that first so the water draining cycles will also reduce the metal levels in the water.

I am new to pools, but I have been doing a lot of reading so I guess I'm mostly looking for verification that I am on the right track.

Current test results:
FC: 20
CC: 0
pH: 7.5
TA: 130
CH: 1125 (I think... the test turns dark purple not blue)
CYA: 200-240 (measured between 50 and 60 using 1/4 dilution)

Here is the current staining. The lighter spot in the center of the bottom step is where we tested with a vitamin C tablet. This staining is throughout the whole pool and the walls are stained darker than the bottom.


Here is the AA and metal sequestrant I purchased


This is the algae control stuff left by the previous owner. Is this the same as polyquot? I don't see anything about copper so I'm hoping it's okay to use this while I let my FC level drop


Here is my equipment pad. I'm still working out the logistics of how I'm going to drain. I have a few ideas but I'm more focused on the AA Treatment at the moment.


At this point I just need to wait for my FC level to drop right? I plan on adding the algae control when my FC gets closer to 15 which should be in two days or so.

Thanks! Any help/guidance is appreciated :)
 

pabeader

LifeTime Supporter
TFP Guide
May 14, 2015
4,349
Cartersville Ga
#2
Step away from the Algae Control. All you need is liquid bleach for algae killing. Once it's killed, you will maintain it at the proper level and not worry about algae.

- - - Updated - - -

Your idea about AA then drain has merit. Save the ProTeam until after you do that.

Save the Algae Control if you close in the winter.
 

aeh0603

Well-known member
Apr 6, 2016
115
San Diego, CA
#3
Step away from the Algae Control. All you need is liquid bleach for algae killing. Once it's killed, you will maintain it at the proper level and not worry about algae.
I thought I read that certain algae control products are safe to use during AA Treatment because I have to let the FC level go to 0? Is that not the case? Also, my city requires that pool water have no chlorine and no algae when it's drained to the storm drain and I'm not allowed to drain to the sanitary sewer.
 

pabeader

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TFP Guide
May 14, 2015
4,349
Cartersville Ga
#4
You are correct. You can use it during AA you just don't need to use it normally. You can use the pool water to water the yard. No chlorine and no algae, guess they don't want you drain. :)

Kind of in a hard place, really need to get rid of the metal but can't drain. The other alternative is to use sequestrant to keep the metal from redepositing.
 

duraleigh

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Apr 1, 2007
31,333
Sebring, Florida
#6
OP. all your plans are just fine....nice work thinking it through. Does your fill water test positive for metal?
 

aeh0603

Well-known member
Apr 6, 2016
115
San Diego, CA
#9
FC: 15.5
CC: 0.5

FC is coming down a bit slower than I originally estimated, but it's been overcast lately. I only lost 1ppm FC in the past 24hrs but I'm starting to see dead algae dust in the bottom of the pool. I added 2 cups of the algae control this morning in hopes of keeping my water clear while I let FC go to almost nothing.
 

aeh0603

Well-known member
Apr 6, 2016
115
San Diego, CA
#10
I just tested the water again:

FC: 8
CC: 0.5

That's a lot bigger drop in FC than I expected, is there anything else I can do to prevent algae from taking over? Should I add more of the Algae Control?
 

pabeader

LifeTime Supporter
TFP Guide
May 14, 2015
4,349
Cartersville Ga
#11
Are you seeing any cloudiness?
As long as it's staying clear, you are doing fine. I seem to recall that the algae control will drop the FC a bit on it's own, so that could account for the extra loss.
There are ways to help it along, if you want to get it down faster. I've read that simple hydrogen peroxide will neutralize chlorine at about a 1 to 1 ratio. There is a recent post about it... Isaac-1 wrote "Common Hydrogen Peroxide will also neutralize chlorine, and may be easier to find than sodium thiosulfate. Common drug store (dollar store) hydrogen peroxide neutralizes chlorine on about a 1 to 1 ratio with the rate that common 8% bleach raises it. So if a 8% gallon of bleach / liquid chlorine raises FC by 5 ppm, then a gallon of Hydrogen Peroxide will lower it by roughly 5 ppm. It is not an exact match, but is close enough for our purposes."
 

aeh0603

Well-known member
Apr 6, 2016
115
San Diego, CA
#13
Thank you, yes my water is still clear but i do see a tiny bit of algae in the grout lines and some algae dust on the bottom of the pool. I have been brushing every couple days to try and minimize the algae growth. My chlorine loss was back to the slower rate for yesterday though so that is further evidence that the big drop was from the algae control.

FC: 6.5
CC: 0.5
pH: 7.5

In other news, my dad said he would help me add some valves and a t-joint to the pvc piping between my pump and filter so i have an easier way to drain the pool :) I don't need anything special right? Just the normal joints, valves, and pvc glue sold at Home Depot/Lowes etc.?
 

pooldv

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Aug 10, 2012
24,993
DFW, TX
#14
I wouldn't use the ball valves, they swell internally and stick after a couple of years. Use Jandy or Pentair never lube style valves.
 

aeh0603

Well-known member
Apr 6, 2016
115
San Diego, CA
#15
Great, thanks! I bought this valve, which is getting installed tonight. My FC was 4.5 this morning before I added more Algae Control so it looks like chlorine will be low enough to get started soon. Unfortunately I will be out of town for a couple days so I probably won't start until Sunday. Since I am doing AA and draining water, here is the modified procedure I plan to use:

1. Ensure FC=0 and pH=7.2
2. Run pump 24/7 during AA treatment
3. Drop AA down sides of pool (starting with 0.5-1 lbs AA per 10,000 Gal)
4. Wait 30 min
5. If there is still staining present, add more AA near stain then wait 30 min.
6. When all stains are gone, let pool sit with pump running for 24hrs
7. Do two 50% drain/refill cycles to lower CYA and CH to reasonable levels (this will also reduce metal levels in water)
8. Add Metal Magic
9. Re-balance water and slowly start increasing FC


Does this sound like a good plan? Is anything out of order?
 

aeh0603

Well-known member
Apr 6, 2016
115
San Diego, CA
#16
New valve installed!


Question: I originally tried a 1.5 inch backwash hose since I have 1.5 inch pvc pious, but it was way too small. Evidently that's the width of the flat hose not the open hose... what size do I need to get to fit on 1.5 inch pvc pipes? Will a 2 inch hose be big enough?
 

pooldv

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Aug 10, 2012
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DFW, TX
#17
Nice plumbing work! When I need plumbing stuff I take all my stuff to Lowes and stand around on the plumbing aisle for a while. :mrgreen:
 

aeh0603

Well-known member
Apr 6, 2016
115
San Diego, CA
#18
Progress report: I started the AA Treatment about an hour ago. I started with 1lb of AA, waited 30 min and added a 2nd lb because the stains weren't gone yet (I only bought 2 lbs so adding more isn't an option unless I go back to the store). It's not perfect, but it looks WAY better.



At this point I think I'm going to let the pump run overnight and start draining the pool tomorrow unless any of you experts think otherwise.
 

aeh0603

Well-known member
Apr 6, 2016
115
San Diego, CA
#19
I drained the pool down to the second step this morning. I was going to go down to the bottom step, but had to leave for work. I'm guessing I've drained somewhere between 1/3 and 1/2 the water, but probably closer to 1/3. I now have the garden house on low filling it back up while at work. I will post the new test results when I get home and the pool is full again.

 

aeh0603

Well-known member
Apr 6, 2016
115
San Diego, CA
#20
Pool is refilled, I ran all the tests after the water had some time to circulate.

Starting values from 5/3/16:
FC: 20
CC: 0
pH: 7.5
TA: 130
CH: 1125 (I think... the test turns dark purple not blue)
CYA: 200-240 (measured between 50 and 60 using 1/4 dilution)

Right before AA treatment values (5/15/16):
FC: 1
CC: 0.5
pH: 7.4

Current values (5/16/16):
FC: 0
CC: 0
pH: 7.4
TA: 110
CH: 700 (I think, I still have a hard time with the end point of this one)
CYA: 180 (measured 90 with 1/2 dilution)

Either I didn't drain as much water as I thought, or my CYA was higher than I thought :( Based on CH and some algebra I drained about 50% of the water so I was expecting CYA to be closer to 120, but that's only if my CH measurements are accurate... off to drain more water...