ACV rinsing?

[gothicchick]

hi, i would just like to know abit more about ACV rinses? i've heard their only for dark hair, so what could be suggested for blonde hair to possibly help with lightening? what are the benefits of ACV rinses, and what hair types do they suit?

just any personal experiences and tips will be helpful, thanks :):cheese:

[pepperminttea]

ACV can add a red tinge to your hair over time, that's why blondes may want to avoid it. You can use white vinegar which won't leave a colour. I don't think it does anything to lighten your hair though? If you want to lighten your hair, I'd look into honey lightening, or coconut oilings before bleaching, but bear in mind to lighten your hair drastically (ie. more than a shade or two) can be significantly damaging, even with a 'natural' method. If you're okay with that, go ahead, but it's something to be aware of. :)

Back to ACV rinses: If you wash with an shampoo bar particularly, those are very alkaline, and the scalp is naturally a little acidic. A lot of people use a dilute acidic rinse to reset their scalp back to it's comfortable pH level after washing. :) Personally I use it because my scalp seems happier when I do, it's also a mild chelator (removes some mineral build-up) which helps with hard water, and it adds a bit of shine too. The thing I would say is though, start with weaker dilutions, and don't go above 50:50 ratio of ACV to water. The scent hangs around more at higher dilutions too, whereas it will go when the hair dries at weaker dilutions.

[gothicchick]

ACV can add a red tinge to your hair over time, that's why blondes may want to avoid it. You can use white vinegar which won't leave a colour. I don't think it does anything to lighten your hair though? If you want to lighten your hair, I'd look into honey lightening, or coconut oilings before bleaching, but bear in mind to lighten your hair drastically (ie. more than a shade or two) can be significantly damaging, even with a 'natural' method. If you're okay with that, go ahead, but it's something to be aware of. :)

Back to ACV rinses: If you wash with an shampoo bar particularly, those are very alkaline, and the scalp is naturally a little acidic. A lot of people use a dilute acidic rinse to reset their scalp back to it's comfortable pH level after washing. :) Personally I use it because my scalp seems happier when I do, it's also a mild chelator (removes some mineral build-up) which helps with hard water, and it adds a bit of shine too. The thing I would say is though, start with weaker dilutions, and don't go above 50:50 ratio of ACV to water. The scent hangs around more at higher dilutions too, whereas it will go when the hair dries at weaker dilutions.

ok thanks :) how do i go about mixing the solution? and how do i apply it?

[heidi w.]

Generally, based on my personal experience, I recommend blondes interested in performing a vinegar rinse use White Distilled Vinegar, not Apple Cider Vinegar, because with prolonged use, Apple Cider Vinegar can tinge the hair with some red tones.

Either vinegar will provide just about the same benefits overall; the difference is that white vinegar doesn't have "apple" in it, meaning there's no malic acid which is said to be beneficial for the health of scalp skin. Some people use vinegar rinses elsewhere on their body, and in some cases, it can assist with problems concerning body odor.

There have been numerous threads and articles regarding Apple Cider Vinegar rinses (ACV rinses). As with everything regarding hair, some people have a positive experience; some people don't have a positive experience.

ACV rinses are often discussed in conjunction with Baking Soda hair washes, which I reserve not for a normal hair wash -- which some people do -- but use it for a "clarifying" hair wash.

Clarifying is a term to mean that one is removing everything that's layered on top of the cuticle of hair: product, built up hard water minerals, oils, conditioner, etc. Everything. NEVER, EVER put on baking soda and any vinegar mixed together nor at the same time (even if not mixed together) on the hair. This formula of mixing the two is for removing nasty drain clogs. You don't want to lose your hair by accident. You probably won't lose it, but you may notice a suddenly big shed. Use these products separately in hair washing.

The proper way to use any vinegar recipe is heavily and well-diluted. I recommend 3 Tablespoons of vinegar (white or ACV) in a cup (8 oz) of water. Different folks offer different dilution ratios because some are using gallons instead of ounces, for example.

But this thread is only about the question of vinegar rinses, so I will stick to just that topic, the benefits of vinegar rinses.

--balances pH of the scalp skin to a more neutral position, around 7.0 on the pH scale. Shampoo and conditioners tend to create a more alkalai state of pH (on some scales alkalai is also called "base"), on that spectrum of the pH scale. The goal of vinegar is to nudge things a bit more toward the acidic end of the spectrum, winding up at something around "neutral" on the scale, say 6.8 - 7.0 on the pH scale. You can search on the internet to have a looksee at a picture of the pH scale.

--removes product left remaining on the hair in that specific hair wash only. Some claim vinegar rinses to be "clarifying" but once anything has dried on your hair, vinegar rinses cannot typically remove it. For that you likely need to clarify.

--removes hard water minerals remaining from that hair wash.

--for some it can assist or aide in coping with dandruff, and some even claim it cures their dandruff. I have Seborrheic Dermatitus, a nasty form of dandruff, and vinegar rinses merely manage my symptoms somewhat. No cure for me anywhere.

--most use the vinegar rinse between shampooing and conditioning; when I used it, I did it after conditioning, otherwise you're adding product after the vinegar rinse.

--Apple Cider Vinegar is diluted the same per above. Any vinegar rinse is a RINSE. It is NOT meant to remain on the hair for any specific duration of time, and definitely rinse it out. Do not apply and leave it in the hair. You'll have tacky, tangly, weird hair behavior.

I'm sure others will reply here with more personal experiences. But this is the overview of benefits. Since you're asking this question, might I suggest you look into acquiring the book Naturally Healthy Hair by Mary Beth Janssen. There are other books with a similar title, but this book is fabulous. The opening discusses how hair grows and the Ayurvedic principles upon which this author bases her text. The text is well-informed. The middle section has tons of home recipes you can make yourself for rinses, conditioners, and shampoos. The last section is about styling. It's one of my hair bibles. Usually one has to order this book from a supplier; it's not typically on bookshelves in bookstores. I don't know if it may be available in your local library, even.

Here's a link to see what the cover looks like:
http://www.amazon.com/Naturally-Healthy-Hair-Treatments-Fabulous/dp/158017129X

I hope this helps a bit,
heidi w.

[spidermom]

I use a much weaker white vinegar rinse, about 1 tbsp to 2-3 quarts of water (a juice pitcher).

[heidi w.]

It's applied by pouring the concoction over your head of hair, and then I used to make a second cup to dunk my length in. I would make it before washing my hair. Watch out, it's cold or cooler. In winter, this is kind of not very fun.

heidi w.

[heidi w.]

I use a much weaker white vinegar rinse, about 1 tbsp to 2-3 quarts of water (a juice pitcher).

This is fine, the main thing is that it's well-diluted. Never pour straight vinegar of any sort on your hair. Never use Balsamic Vinegar as it has sugar in it and that could be a pain to deal with.

Some scalps are fine and only need a little bit. Some need more, such as mine with this nasty Seborrheic Dermatitus.

heidi w.

[gothicchick]

Generally, based on my personal experience, I recommend blondes interested in performing a vinegar rinse use White Distilled Vinegar, not Apple Cider Vinegar, because with prolonged use, Apple Cider Vinegar can tinge the hair with some red tones.

Either vinegar will provide just about the same benefits overall; the difference is that white vinegar doesn't have "apple" in it, meaning there's no malic acid which is said to be beneficial for the health of scalp skin. Some people use vinegar rinses elsewhere on their body, and in some cases, it can assist with problems concerning body odor.

There have been numerous threads and articles regarding Apple Cider Vinegar rinses (ACV rinses). As with everything regarding hair, some people have a positive experience; some people don't have a positive experience.

ACV rinses are often discussed in conjunction with Baking Soda hair washes, which I reserve not for a normal hair wash -- which some people do -- but use it for a "clarifying" hair wash.

Clarifying is a term to mean that one is removing everything that's layered on top of the cuticle of hair: product, built up hard water minerals, oils, conditioner, etc. Everything. NEVER, EVER put on baking soda and any vinegar mixed together nor at the same time (even if not mixed together) on the hair. This formula of mixing the two is for removing nasty drain clogs. You don't want to lose your hair by accident. You probably won't lose it, but you may notice a suddenly big shed. Use these products separately in hair washing.

The proper way to use any vinegar recipe is heavily and well-diluted. I recommend 3 Tablespoons of vinegar (white or ACV) in a cup (8 oz) of water. Different folks offer different dilution ratios because some are using gallons instead of ounces, for example.

But this thread is only about the question of vinegar rinses, so I will stick to just that topic, the benefits of vinegar rinses.

--balances pH of the scalp skin to a more neutral position, around 7.0 on the pH scale. Shampoo and conditioners tend to create a more alkalai state of pH (on some scales alkalai is also called "base"), on that spectrum of the pH scale. The goal of vinegar is to nudge things a bit more toward the acidic end of the spectrum, winding up at something around "neutral" on the scale, say 6.8 - 7.0 on the pH scale. You can search on the internet to have a looksee at a picture of the pH scale.

--removes product left remaining on the hair in that specific hair wash only. Some claim vinegar rinses to be "clarifying" but once anything has dried on your hair, vinegar rinses cannot typically remove it. For that you likely need to clarify.

--removes hard water minerals remaining from that hair wash.

--for some it can assist or aide in coping with dandruff, and some even claim it cures their dandruff. I have Seborrheic Dermatitus, a nasty form of dandruff, and vinegar rinses merely manage my symptoms somewhat. No cure for me anywhere.

--most use the vinegar rinse between shampooing and conditioning; when I used it, I did it after conditioning, otherwise you're adding product after the vinegar rinse.

--Apple Cider Vinegar is diluted the same per above. Any vinegar rinse is a RINSE. It is NOT meant to remain on the hair for any specific duration of time, and definitely rinse it out. Do not apply and leave it in the hair. You'll have tacky, tangly, weird hair behavior.

I'm sure others will reply here with more personal experiences. But this is the overview of benefits. Since you're asking this question, might I suggest you look into acquiring the book Naturally Healthy Hair by Mary Beth Janssen. There are other books with a similar title, but this book is fabulous. The opening discusses how hair grows and the Ayurvedic principles upon which this author bases her text. The text is well-informed. The middle section has tons of home recipes you can make yourself for rinses, conditioners, and shampoos. The last section is about styling. It's one of my hair bibles. Usually one has to order this book from a supplier; it's not typically on bookshelves in bookstores. I don't know if it may be available in your local library, even.

Here's a link to see what the cover looks like:
http://www.amazon.com/Naturally-Healthy-Hair-Treatments-Fabulous/dp/158017129X

I hope this helps a bit,
heidi w.

thank you very much for the info!! i must see into getting that book. ;)

[heidi w.]

FYI: vinegar is a form of "acid". Other things can be used besides vinegar, such as lemon juice, in the same dilution ratio. I am completely not aware of any lightening effects from white vinegar. I've never read any such claims anywhere.

heidi w.

[pepperminttea]

how do i go about mixing the solution? and how do i apply it?

heidi w. covered it insanely well, but since you asked; I have an old 8oz/227ml conditioner bottle, and I put a funnel in the top, and measure out and add four dessert spoons of ACV to the bottle. I take the funnel out, and fill the rest of the bottle with water. Lid on, shake bottle, ready. :D

When I'm in the shower, after I've washed my hair but before I condition, I squeeze it over my head, focusing mainly on my scalp, and gently massaging with my fingers to make sure it gets through. (Make sure you tip your head back so it doesn't go in your eyes, it stings!) Then I rinse it out thoroughly, and condition as normal. :)

ps. There's also some lemon rinse info here (http://forums.longhaircommunity.com/showthread.php?t=53745).

[heidi w.]

Back to ACV rinses: If you wash with an shampoo bar particularly, those are very alkaline, and the scalp is naturally a little acidic. A lot of people use a dilute acidic rinse to reset their scalp back to it's comfortable pH level after washing. :) Personally I use it because my scalp seems happier when I do, it's also a mild chelator (removes some mineral build-up) which helps with hard water, and it adds a bit of shine too. The thing I would say is though, start with weaker dilutions, and don't go above 50:50 ratio of ACV to water. The scent hangs around more at higher dilutions too, whereas it will go when the hair dries at weaker dilutions.

Underscore added by heidi w. so folks will know what I'm talking about and referring to.


Um, chelating is very different from clarifying. Clarifying removes buildup of stuff on top of the hair's cuticle. Chelating (pronounced keylating) is a chemistry term and means to remove anything bonded inside the hair, at the cortex level. For example, a lot of salons chelate hair prioir to a perm or color application to help ensure things go well in the application.

What's described here is clarifying, not chelatingOther benefits I just remembered of vinegar rinses:

--can improve shine a tiny bit. Your hair won't glare as in TV commercials, but it might be nudged a bit.

--closes the cuticle (as apparently can a cooldown rinse, as long as the temp of the water is cooler than washing temp).

--"binds" the cuticle meaning it helps the cuticle to close a bit which in turn can improve shine a bit.

There was something else I was going to mention, but I forgot it already. There's a bit of noise in the wifi cafe that I'm hanging in. IF I remember, I'll write in again.

ETA: Ah! "Buildup" is a term you will see used in discussing clarifying and vinegar rinses. Buildup means pretty much that: stuff kind of built up on top of the cuticle (outer layer we see, the shell) of hair. Bonds to the cortex we don't see so much, but we notice the change in hair's behavior. Year's ago a young lady here on LHC had a salt bond to the cortex, and chelating saved her hair. Her hair was behaving entirely oddly. END ETA
heidi w.

[gothicchick]

heidi w. covered it insanely well, but since you asked; I have an old 8oz/227ml conditioner bottle, and I put a funnel in the top, and measure out and add four dessert spoons of ACV to the bottle. I take the funnel out, and fill the rest of the bottle with water. Lid on, shake bottle, ready. :D

When I'm in the shower, after I've washed my hair but before I condition, I squeeze it over my head, focusing mainly on my scalp, and gently massaging with my fingers to make sure it gets through. (Make sure you tip your head back so it doesn't go in your eyes, it stings!) Then I rinse it out thoroughly, and condition as normal. :)

ps. There's also some lemon rinse info here (http://forums.longhaircommunity.com/showthread.php?t=53745).

thank you :)

[pepperminttea]

Um, chelating is very different from clarifying. Clarifying removes buildup of stuff on top of the hair's cuticle. Chelating (pronounced keylating) is a chemistry term and means to remove anything bonded inside the hair, at the cortex level. For example, a lot of salons chelate hair prioir to a perm or color application to help ensure things go well in the application.

From how I (thought I) understood it, clarifying was removing typical build-up like sebum, wax, silicone, and product build-up, whereas chelating was for removing mineral build-up, like hard water residue and chlorine?

If not, I'd love to learn. :)

[gothicchick]

Underscore added by heidi w. so folks will know what I'm talking about and referring to.


Um, chelating is very different from clarifying. Clarifying removes buildup of stuff on top of the hair's cuticle. Chelating (pronounced keylating) is a chemistry term and means to remove anything bonded inside the hair, at the cortex level. For example, a lot of salons chelate hair prioir to a perm or color application to help ensure things go well in the application.

What's described here is clarifying, not chelatingOther benefits I just remembered of vinegar rinses:

--can improve shine a tiny bit. Your hair won't glare as in TV commercials, but it might be nudged a bit.

--closes the cuticle (as apparently can a cooldown rinse, as long as the temp of the water is cooler than washing temp).

--"binds" the cuticle meaning it helps the cuticle to close a bit which in turn can improve shine a bit.

There was something else I was going to mention, but I forgot it already. There's a bit of noise in the wifi cafe that I'm hanging in. IF I remember, I'll write in again.

ETA: Ah! "Buildup" is a term you will see used in discussing clarifying and vinegar rinses. Buildup means pretty much that: stuff kind of built up on top of the cuticle (outer layer we see, the shell) of hair. Bonds to the cortex we don't see so much, but we notice the change in hair's behavior. Year's ago a young lady here on LHC had a salt bond to the cortex, and chelating saved her hair. Her hair was behaving entirely oddly. END ETA
heidi w.

ahh i see, ok thank you :)

i will definately give it a try, with the white vinegar instead though,

[heidi w.]

Sorry Peppermint Tea. Clarifying also covers the hard water mineral buildup on TOP of the hair's cuticle. I personally don't mind learning new stuff. So I hope I've been a little bit helpful. I hope I didn't cause any offense.

heidi w.

[pepperminttea]

Sorry Peppermint Tea. Clarifying also covers the hard water mineral buildup on TOP of the hair's cuticle. I personally don't mind learning new stuff. So I hope I've been a little bit helpful. I hope I didn't cause any offense.

heidi w.

No no, not at all; you learn something new everyday and all that. :) So does chelating take out mineral build-up beneath the cuticle instead?

[gothicchick]

Underscore added by heidi w. so folks will know what I'm talking about and referring to.


Um, chelating is very different from clarifying. Clarifying removes buildup of stuff on top of the hair's cuticle. Chelating (pronounced keylating) is a chemistry term and means to remove anything bonded inside the hair, at the cortex level. For example, a lot of salons chelate hair prioir to a perm or color application to help ensure things go well in the application.

What's described here is clarifying, not chelatingOther benefits I just remembered of vinegar rinses:

--can improve shine a tiny bit. Your hair won't glare as in TV commercials, but it might be nudged a bit.

--closes the cuticle (as apparently can a cooldown rinse, as long as the temp of the water is cooler than washing temp).

--"binds" the cuticle meaning it helps the cuticle to close a bit which in turn can improve shine a bit.

There was something else I was going to mention, but I forgot it already. There's a bit of noise in the wifi cafe that I'm hanging in. IF I remember, I'll write in again.

ETA: Ah! "Buildup" is a term you will see used in discussing clarifying and vinegar rinses. Buildup means pretty much that: stuff kind of built up on top of the cuticle (outer layer we see, the shell) of hair. Bonds to the cortex we don't see so much, but we notice the change in hair's behavior. Year's ago a young lady here on LHC had a salt bond to the cortex, and chelating saved her hair. Her hair was behaving entirely oddly. END ETA
heidi w.

can i buy the white vinegar just from the supermarket?

[heidi w.]

can i buy the white vinegar just from the supermarket?

Yes.

heidi w.

[heidi w.]

No no, not at all; you learn something new everyday and all that. :) So does chelating take out mineral build-up beneath the cuticle instead?

IF it's bonded with the interior of the hair, such as the cortex, yes.

heidi w.

[pepperminttea]

IF it's bonded with the interior of the hair, such as the cortex, yes.

heidi w.

Ah, I see! Thanks! :D

[heidi w.]

Now, for heavy swimmers, for chlorine, there are swimmer's shampoos to help keep the chlorine at bay. They work, more or less. Depends on how much you swim and how chlorinated the water you swim in is.

For chlorine, chelating may sometimes be the better option over clarifying though.

I always recommend clarifying at least twice BEFORE advancing to chelating.

heidi w.

[gothicchick]

Now, for heavy swimmers, for chlorine, there are swimmer's shampoos to help keep the chlorine at bay. They work, more or less. Depends on how much you swim and how chlorinated the water you swim in is.

For chlorine, chelating may sometimes be the better option over clarifying though.

I always recommend clarifying at least twice BEFORE advancing to chelating.

heidi w.

how do i chelate?
sorry i'm afraid i don't know much about it

[heidi w.]

YOu go shopping for a shampoo product that has the word "Chelate" on the label, and wash your hair with that.

However, I tend to advise that one can usually do fine if they clarify. That resolves most problems. So clarify first, or at least two times, before opting to advance to chelating.

heidi w.

[gothicchick]

YOu go shopping for a shampoo product that has the word "Chelate" on the label, and wash your hair with that.

However, I tend to advise that one can usually do fine if they clarify. That resolves most problems. So clarify first, or at least two times, before opting to advance to chelating.

heidi w.
i see, ok thank you :)

[morrigan*]

It's wrong if i don't rinse out very mild mix of acv rinse ?

[Nae]

It's wrong if i don't rinse out very mild mix of acv rinse ?

Sometimes I leave my acv rinse on my hair, sometimes I don't. I haven't noticed a big difference either way but I have a very mild dilution, about a tablespoon to 12 ounces of water.

[morrigan*]

Sometimes I leave my acv rinse on my hair, sometimes I don't. I haven't noticed a big difference either way but I have a very mild dilution, about a tablespoon to 12 ounces of water.
I ask because i did this last time and my hair was incredibly soft.

[Nae]

I ask because i did this last time and my hair was incredibly soft.

If it works for you, go for it!

[ktani]

I see no harm in leaving a well diluted vinegar rinse in the hair. It comes down to preference. Members here have done that for years with no damaging effects.

More on vinegar can be found here, http://forums.longhaircommunity.com/vbjournal.php?do=article&articleid=184

You can chelate easily and cheaply with a diluted lemon juice rinse, rather than buy a special shampoo for that.

For neutralizing chlorine after swimming, you can use club soda, http://forums.longhaircommunity.com/vbjournal.php?do=article&articleid=115

[morrigan*]

Okay, thank you Nae and Ktani.

[ktani]

Okay, thank you Nae and Ktani.

For my part, you are very welcome. :)

[heidi w.]

It's wrong if i don't rinse out very mild mix of acv rinse ?

I don't like to use the word "wrong". In another thread on the Mane Forum regarding ACV Rinses, I learned some people are leaving it ON the hair to dry on the hair, and apparently they're doing fine. So it does work for some hair types. But the majority experience is that it's a negative experience.

But understand that fundamentally a rinse is intended to be rinsed out. That's what the name rinse means.

In hair care, while it may not seem to make sense, generally, more is not better.

Dilution ratio can affect the outcome of leaving any vinegar rinse on the hair to dry on the hair.

I can say I've never left it on, and never would.

heidi w.

[ktani]

I don't like to use the word "wrong". In another thread on the Mane Forum regarding ACV Rinses, I learned some people are leaving it ON the hair to dry on the hair, and apparently they're doing fine. So it does work for some hair types. But the majority experience is that it's a negative experience.

But understand that fundamentally a rinse is intended to be rinsed out. That's what the name rinse means.

In hair care, while it may not seem to make sense, generally, more is not better.

Dilution ratio can affect the outcome of leaving any vinegar rinse on the hair to dry on the hair.

I can say I've never left it on, and never would.

heidi w.

I have not seen any reports of leaving a diluted vinegar rinse in the hair here having a negative result.

Can you direct me to the majority you speak of please?

[ktani]

I got curious.

As I said I see no point in leaving one in. However, the practice is more common than I thought. See the last post, http://www.longhaircareforum.com/showthread.php?t=565569

ETA: It is not the last post now and there is a very good discussion on dilution and hair porosity.

7 years is a long time for no negative results.

ETA:2 The dilution used is very weak though.

ETA:3 If a solution that has a pH below 3.5 is used on the hair frequently, it can be damaging. In other words, err on the side of a weaker not stronger dilution with both lemon juice or vinegar or buy pH test strips and test the pH of the final mix ETA:4 and that applies whether the solution is left in or rinsed out. A too strong acidic rinse can be damaging rinsed out too.

[Nae]

Okay, thank you Nae and Ktani.

Anytime! Helping out is fun!:D

[gothicchick]

I got curious.

As I said I see no point in leaving one in. However, the practice is more common than I thought. See the last post, http://www.longhaircareforum.com/showthread.php?t=565569

ETA: It is not the last post now and there is a very good discussion on dilution and hair porosity.

7 years is a long time for no negative results.

ETA:2 The dilution used is very weak though.

ETA:3 If a solution that has a pH below 3.5 is used on the hair frequently, it can be damaging. In other words, err on the side of a weaker not stronger dilution with both lemon juice or vinegar or buy pH test strips and test the pH of the final mix ETA:4 and that applies whether the solution is left in or rinsed out. A too strong acidic rinse can be damaging rinsed out too.

what should the ph of the rinse be?

[heidi w.]

I have not seen any reports of leaving a diluted vinegar rinse in the hair here having a negative result.

Can you direct me to the majority you speak of please?

I cannot because I've been merely listening to this and one other board for well over ten years now, and this is the feedback that I have read.

heidi w.

[ktani]

I cannot because I've been merely listening to this and one other board for well over ten years now, and this is the feedback that I have read.

heidi w.

Judging from the other board I posted a link to, it is the dilution used that would be the problem with leaving the rinse in and in most cases I am pretty sure that would apply to the same dilution rinsed out.

Acids like acetic acid (vinegar) and citric and ascorbic acids, which are Alpha Hydroxy acids (lemon juice) are corrosive. When diluted at a pH that is hair and skin friendly, above pH 3.5 they are fine and serve to make skin and hair soft, reacidify both after an alkaline soap is used, and close hair cuticles. Lemon juice diluted, also chelates metal salts.

So I think that it comes down to how the rinse is made, not how it is used.

I do get where you are coming from. I was surprised to read here that people added vinegar to a herb tea and left the solution in their hair. I have not found reports here to say there were problems doing so, or just leaving a diluted vinegar rinse in the hair. I may have missed those posts.

The other forum does have a few such posts.

ETA: This rinse also surprised me left in, until I looked at the dilution, which breaks down approximately (the original recipe is an estimate), to 1 tsp to about 16 oz of water or 500 ml, http://forums.longhaircommunity.com/showthread.php?t=53745
It was too strong for at least one person here. However, it can be adjusted with more water. Thread tips here, http://ktanihairsense.blogspot.com/2010/08/another-cost-effective-innovation-by.html

[ktani]

what should the ph of the rinse be?

pH 3.5 and above - 4.5 preferably, in my opinion.

ETA: The average pH of the acid mantle of skin, and that would include sebum on the scalp is pH 4.7
http://www.ncbi.nlm.nih.gov/pubmed/18489300
"... it is estimated that the 'natural' skin surface pH is on average 4.7, i.e. below 5."

[morrigan*]

When i first leave it on I make it much weaker than when I would rinse it out.
For me is good beacuse my hair tangles less, they are more shiny and very soft. Also we have pretty hard water.

[fridgee]

I always left it on because we have hard water so rinsing it out would just reintroduce the stuff the ACV was trying to get rid of so it seemed counterproductive to me. I do use a weak solution though, only 1-2 tbsp in an at least pint sized cup.