First time Ascorbic Acid treatment -- Should I use a sequestrant, CuLator, or both?

[peterl1365]

I did a spot test with AA from Duda, and it seems to be effective. I'm gonna wait about another week to let my FC drop near zero, and I figured I could do some prep in the meantime. I've read through the guide a couple of times and will reread it a few more times.

I'd prefer to pull the metals out of the water rather than just tie them up in solution (which would require indefinite maintenance dosing). Would the CuLator alone be effective in doing this? For logistical reasons, draining and filling is not a great option. I don't mind spending a bit for 2-3 CuLator packs if I can avoid having to constantly add sequestrants.

Also, a somewhat related question: Does the AA remove stains from the walls? I thought that the crystals sat on the floor and acted locally, so I'm confused about what to do with vertical surfaces. Does the AA go into solution and work on all surfaces simultaneously?

I am on city water (mostly from underground sources, I think). I'll have to see if I can find a recent water report from my supplier.

Any thoughts or opinions?

 

[JoyfulNoise]

I will be the first to say that CuLator's are worthless and sold as a "magic bag of beans" to unsuspecting/unknowing individuals. There is no way a small pouch of ion exchange resin (which is all that it really is) sitting in the skimmer or the strainer basket will be able to pull enough metal out of solution to make any difference. The laws of physics and chemistry, and hydraulics, just don't work like that. They are a waste of money.

Your only viable option is draining the pool and refilling with fresh, metal free water. I realize that it is not always optimal or easy to do that in a lot of circumstances, but that is the only way to get rid of the metal ions that will be returned to solution once you use the ascorbic acid. Sorry, but that IS the reality of the laws of chemistry and physics.

The AA, once dissolved and fully mixed into the pool water volume, will remove stains on all surfaces. The problem you are seeing is that your water is cold and you simply broadcasted the granules onto the water where they sunk to the bottom. The granules slowly dissolved and, with little mixing, created a concentrated solution around them that lifted the stains locally. When you do this process for real, I would suggest pre-dissolving the AA in a bucket of warm water and then dispersing it in front of the returns. You can use a a sock or nylon filled with the granules to act like poultice to scrub areas that have heavy staining, but the majority of the work will be dissolving the AA and homogenizing/mixing the pool water thoroughly. This is always A LOT harder when water is cold.

Be very careful to isolate your equipment pad from the AA water. AA is bad for heaters and so you need to be able to bypass the heater or remove it some service BEFORE you apply AA.

 

[mknauss]

I am on city water (mostly from underground sources, I think). I'll have to see if I can find a recent water report from my supplier.

I would suspect a significant portion of your water source is the Colorado River. That is the source of iron.

 

[peterl1365]

I will be the first to say that CuLator's are worthless and sold as a "magic bag of beans" to unsuspecting/unknowing individuals. There is no way a small pouch of ion exchange resin (which is all that it really is) sitting in the skimmer or the strainer basket will be able to pull enough metal out of solution to make any difference. The laws of physics and chemistry, and hydraulics, just don't work like that. They are a waste of money.

Your only viable option is draining the pool and refilling with fresh, metal free water. I realize that it is not always optimal or easy to do that in a lot of circumstances, but that is the only way to get rid of the metal ions that will be returned to solution once you use the ascorbic acid. Sorry, but that IS the reality of the laws of chemistry and physics.

The AA, once dissolved and fully mixed into the pool water volume, will remove stains on all surfaces. The problem you are seeing is that your water is cold and you simply broadcasted the granules onto the water where they sunk to the bottom. The granules slowly dissolved and, with little mixing, created a concentrated solution around them that lifted the stains locally. When you do this process for real, I would suggest pre-dissolving the AA in a bucket of warm water and then dispersing it in front of the returns. You can use a a sock or nylon filled with the granules to act like poultice to scrub areas that have heavy staining, but the majority of the work will be dissolving the AA and homogenizing/mixing the pool water thoroughly. This is always A LOT harder when water is cold.

Be very careful to isolate your equipment pad from the AA water. AA is bad for heaters and so you need to be able to bypass the heater or remove it some service BEFORE you apply AA.

Thank you for the insights. I guess I will try a sequestering agent first. What type of concentration rise do you think I might see without doing anything. I had my water measured at Leslies (I know, I know, but I don't have any other way or measuring metals), and it came back as 0.1 ppm each of iron and copper. After AA, would this increase by 10x? 50x? Just wondering the magnitude of the metals that will be in solution. I can replace some of the water (maybe 10-20%), but it's not really feasible to do more. I do this occasionally any way to reduce hardness.

Thanks for clarifying how the AA works on walls. I'm always skeptical of pool chemicals, and it didn't seem like 1-2 lbs dissolved in 10,000 gal of water would be concentrated enough to really do anything. I've always heard about using Vitamin C tablets, so I assumed that a very high concentration would be needed to actually break down stains. Do you think 2 lbs is enough for a ~14,000 gallon plaster pool? A lot of the testimonials I've seen on Youtube are for liner pools. I wonder if I should just get some more.

Should I keep the water circulating during treatment or just let it soak? Seems to me that circulating would be more effective for getting stains off vertical surfaces.

That's also a good tip regarding my heater. Fortunately, I have my system plumbed in such a way that I can bypass my heater when I'm not using it (99.9 % of the time).

 

[peterl1365]

I would suspect a significant portion of your water source is the Colorado River. That is the source of iron.

You're probably right. Just not sure because So. Cal. gets water from a number of different sources, and the CO river has been cutting back deliveries because of the western drought. FWIW, I found the water quality report for my agency, but they don't list iron levels. My Leslies pool store measured my pool water at 0.1 ppm, which is half of their recommended maximum.

 

[mknauss]

EPA does not require iron levels to be reported.

 

[mknauss]

Can you post a full set of water chemistry results from a proper test kit?

 

[Bperry]

Thank you for the insights. I guess I will try a sequestering agent first. What type of concentration rise do you think I might see without doing anything. I had my water measured at Leslies (I know, I know, but I don't have any other way or measuring metals), and it came back as 0.1 ppm each of iron and copper. After AA, would this increase by 10x? 50x? Just wondering the magnitude of the metals that will be in solution. I can replace some of the water (maybe 10-20%), but it's not really feasible to do more. I do this occasionally any way to reduce hardness.

Thanks for clarifying how the AA works on walls. I'm always skeptical of pool chemicals, and it didn't seem like 1-2 lbs dissolved in 10,000 gal of water would be concentrated enough to really do anything. I've always heard about using Vitamin C tablets, so I assumed that a very high concentration would be needed to actually break down stains. Do you think 2 lbs is enough for a ~14,000 gallon plaster pool? A lot of the testimonials I've seen on Youtube are for liner pools. I wonder if I should just get some more.

Should I keep the water circulating during treatment or just let it soak? Seems to me that circulating would be more effective for getting stains off vertical surfaces.

That's also a good tip regarding my heater. Fortunately, I have my system plumbed in such a way that I can bypass my heater when I'm not using it (99.9 % of the time).

The Leslie’s metal tests have a tolerance of +\-0.3ppm, at 0.3, for metals so they essentially tested yours at zero. I filled my pool from scratch and they tested my water at 0.2 and 0.4 (same water, tested at different stores). So their metals tests is pretty useless.

 

[duraleigh]

A whole house water softener for your refill water would eliminate the need for a sequestrant.

 

[peterl1365]

The Leslie’s metal tests have a tolerance of +\-0.3ppm, at 0.3, for metals so they essentially tested yours at zero. I filled my pool from scratch and they tested my water at 0.2 and 0.4 (same water, tested at different stores). So their metals tests is pretty useless.

Yeah, their results are pretty questionable. I basically use their tests as a rough guide and sanity check for my own testing (which is also suspect). I generally just shoot for a range and I don't really have any problems. Still, it's nice to know that the fill water is relatively low. The stains I want to remove have accumulated over the course of more than 15 years.

 

[peterl1365]

A whole house water softener for your refill water would eliminate the need for a sequestrant.

Maybe, but my autofill comes from a separate water supply. The main is branched to an irrigation line before the water enters the house. I don't really want a softener just for the pool, and it would take a fair bit of plumbing to install the softener between the sprinkler manifold and the autofill. Aside from that, I dislike soft water because I hate the feeling of soap not washing off my body.

 

[peterl1365]

Can you post a full set of water chemistry results from a proper test kit?

Unfortunately, I don't use a proper test kit. I'm color blind, so I just use a TruTest strip reader to get keep my FC and PH in range. It's generally good enough for my purposes.

 

[mknauss]

Unfortunately, I don't use a proper test kit. I'm color blind, so I just use a TruTest strip reader to get keep my FC and PH in range. It's generally good enough for my purposes.

Only test that is an issue for color blind is pH. And there are quality digital pH testers (expensive).

Poor management of pH and FC can exacerbate iron staining.

 

[peterl1365]

Only test that is an issue for color blind is pH. And there are quality digital pH testers (expensive).

Poor management of pH and FC can exacerbate iron staining.

You may be right. I've constantly fought rising pH over the years. I generally add acid on a weekly basis to keep pH in the 7.5-7.8 range, and I've added borates to establish a buffer. It could probably use some more borates, which I hope to bolster with the addition of 20 Mule Borax after the AA treatment.

 

[Bperry]

You may be right. I've constantly fought rising pH over the years. I generally add acid on a weekly basis to keep pH in the 7.5-7.8 range, and I've added borates to establish a buffer. It could probably use some more borates, which I hope to bolster with the addition of 20 Mule Borax after the AA treatment.

The TFP recommended test kits is way easier to use than all those other, even if you are color blind. Lots of people have that fear and realize it’s unfounded once they try it. If you can see the difference between clear liquid and pink (shade doesn’t matter), or whether a sample is either green or red, you’ll be able to use the kit.

 

[Newdude]

I don't use a proper test kit. I'm color blind, so I just use a TruTest strip reader

You can see color change and that's all you need. You can call it blue and I can call it pink and we BOTH know it isn't clear. Or green to red, yellow to brick red, etc.. It doesn't matter if you see it as light gray to dark gray, you'll see the change and know it did the thing.

 

[peterl1365]

You can see color change and that's all you need. You can call it blue and I can call it pink and we BOTH know it isn't clear. Or green to red, yellow to brick red, etc.. It doesn't matter if you see it as light gray to dark gray, you'll see the change and know it did the thing.

Well, green to red is the problem. That is the most common form of color blindness. I can generally distinguish between bright red and bright green, but when they are both light pastels they are very difficult to distinguish.