I did the Jack's magic stain ID test. It is showing that I have Iron scale. From what I'm seeing on line, I need to bring the PH down while I use these chemicals - should that concern me? - it brings the ph down to the mid 6's. I have a plaster pool -
As long as the duration of low PH remains fairly short, say a couple to four days, and the PH doesn't go too low there is no problem. You don't want to go below perhaps 6.6, and ideally you want to stay up closer to 6.8. Of course you can't always tell just how low the PH ends up, but as long as you follow the directions and are careful not to lower the PH too far at the start things should work out just fine.
editing to ask how I can really determin what my stains are --
- I'm completely conflicted. -- I did the Jack's tests and the copper test showed some reaction, and so did the iron scale. i felt the iron scale was more dramatic. However, my local pool guy says that Iron is unusual to find in this water. He is recommending a no drain acid wash. Again. I'm totally conflicted. Want to clear my pool, but if it's not truly iron, will the acid wash help. I really need some direction. Pool is 11750 gallons, pool guy saying to use about 7 gallons of acid which sounds like way too much ----
Tests were as follows.
cl 5.0
ph 7.2
alk 100
stab. 100
hard. 1000
I know the hardness is too high. Pool guy is saying get it clear and then drain and refill.
- I'm completely conflicted. -- I did the Jack's tests and the copper test showed some reaction, and so did the iron scale. i felt the iron scale was more dramatic. However, my local pool guy says that Iron is unusual to find in this water. He is recommending a no drain acid wash. Again. I'm totally conflicted. Want to clear my pool, but if it's not truly iron, will the acid wash help. I really need some direction. Pool is 11750 gallons, pool guy saying to use about 7 gallons of acid which sounds like way too much ----
Tests were as follows.
cl 5.0
ph 7.2
alk 100
stab. 100
hard. 1000
I know the hardness is too high. Pool guy is saying get it clear and then drain and refill.
If you are not convinced with the Jack's Majic test, you could try the Taylor Copper and Taylor iron test to see if they confirm your results. What color are the stains? Can you post a good pic?
Identifying the stains is crucial to lift them properly.
Identifying the stains is crucial to lift them properly.
Here is a simple way to confirm iron stains. Place a vitamin C tablet on a stained area for 30 seconds. If the stain goes away or at least lightens significantly then it is very likely iron and you should do an iron stain treatment (typical ascorbic acid or citric acid along with sequestrant).
Given your hardness (calcium) level, calcium scaling does seem much more likely than iron. Calcium scale will not react to vitamin C at all, so that test will narrow things down a great deal. Calcium scale tends to be rather rough, while iron stains tend to be smooth, though there are some exceptions. There does remain a chance that you have both iron and calcium, but lets deal with one thing at a time.
A no drain acid wash is one way to deal with calcium scaling. It is a very aggressive treatment and runs some risk of damaging areas of plaster that do not have any calcium scale to begin with. Generally a complete drain and manual acid wash is the preferred approach for calcium scale, though it does cost more/takes way more work.
Given your hardness (calcium) level, calcium scaling does seem much more likely than iron. Calcium scale will not react to vitamin C at all, so that test will narrow things down a great deal. Calcium scale tends to be rather rough, while iron stains tend to be smooth, though there are some exceptions. There does remain a chance that you have both iron and calcium, but lets deal with one thing at a time.
A no drain acid wash is one way to deal with calcium scaling. It is a very aggressive treatment and runs some risk of damaging areas of plaster that do not have any calcium scale to begin with. Generally a complete drain and manual acid wash is the preferred approach for calcium scale, though it does cost more/takes way more work.
I really appreciate all the help. The stains look like dirt in the pool. Since we are in Az., and susceptible to sand storms, that is what we thought it was, until I realized that the cleaner was not getting it up. It is a light brown (sand) color, streaked down the sides, and mottled looking on the floor of the deeper end, looking just like dirt! It feels smooth, does not feel rough to me, and happened overnight - literally. We had backwashed, then filled and shocked and the next day it was there. It has not gotten worse over the 2 weeks it's been there, but has not gotten any better either. I had used "Stain Treat" last week, and it did nothing.
The vitamin C tabs did nothing when I tested them, confirming what the pool guy said - very surprising if it's iron. I took a water sample to another place and had everything tested. Iron was low, copper a little higher. Since we have not drained the pool in a very, very long time, the solids are way too high.
We have decided it's time to drain, and do an acid wash while it is empty.
So, that brings up more questions. What was suggested was a 3-1 ratio of water to acid, and to spray it with a chemical sprayer, then keep it lightly misted so it doesn't dry out. Then brushing it and rinsing. Is this the proper procedure?
Would you suggest something else while it's empty?
The vitamin C tabs did nothing when I tested them, confirming what the pool guy said - very surprising if it's iron. I took a water sample to another place and had everything tested. Iron was low, copper a little higher. Since we have not drained the pool in a very, very long time, the solids are way too high.
We have decided it's time to drain, and do an acid wash while it is empty.
So, that brings up more questions. What was suggested was a 3-1 ratio of water to acid, and to spray it with a chemical sprayer, then keep it lightly misted so it doesn't dry out. Then brushing it and rinsing. Is this the proper procedure?
Would you suggest something else while it's empty?