| Author |
 Topic Search  Topic Options
|
Lowry 
Guest
Joined: March 04 2006
Location: Korea
Status: Offline
Points: 162
|
 Post Options
 Thanks(0)
 Quote  Reply
 Topic: Alkalinity vs. pH
Posted: April 13 2006 at 3:04pm |
So, my husband swears that alkalinity and pH are the same thing. His sicence background gave me a 100% garantee. This is his argument for not getting an alkalinity tester...husbands... After all of the reading I have done, obviously I've figured out they are different, but he will just not listen to me. So, I need your help. Without insulting (I don't want to sleep on the couch) please scientifically explain to him why pH and alkalinity are different. I would greatly appreciate it, plus I get to say, I told you so! 
Sarah Lowry
PM's or emails are fine too
|
|
Moving back to Utah soon, and starting a new tank or three!
|
 |
jfinch
Guest
Joined: March 06 2003
Location: Pleasant Grove
Status: Offline
Points: 7067
|
Post Options
Thanks(0)
Quote Reply
Posted: April 13 2006 at 3:29pm |
pH is a measure of hydronium ions (H3O+ or more commonly refered to as H+) in an aqueous solution. Hydronium is related to hydroxide via water.
H2O = H+ + OH-
pH=-log([H+])
This is where his confusion likely comes from. A pH of 7 is said to be neutral. pH less then 7 is acidic. pH greater then 7 is alkaline. Alkaline describes a pH condition.
Alkalinity is a measure of ions in solution that collectively cause the solution to be alkaline. So... alkalinity does not equal alkaline.
There is another property of water that is called acidity. It is the measure of ions that contribute to the acidic nature of a solution. Since seawater has almost no acidity, it's not important for us, but for some freshwater systems it is.
My advice for presenting this to him: explain it to him about 5 minutes after the two of you crawl into bed. His attention will be on sleep or something else and I find that I'm more receptive to new ideas in either of these condtions.
|
|
|
|
unixnum1
Guest
Joined: January 08 2004
Location: Highland, UT
Status: Offline
Points: 482
|
Post Options
Thanks(0)
Quote Reply
Posted: April 13 2006 at 4:33pm |
|
I was having problems explaining it to a chemist also until I mentioned
what John said and then the chemist said "Ohhh, now I know what you are
talking about"
At that point he understood and could answer my questions.
Good luck
|
220G with 30G sump, SPS/LPS. RoboTank Controller. =====================================
If life is a bowl of cherry's,
why am I always the stem?
|
|
Lowry
Guest
Joined: March 04 2006
Location: Korea
Status: Offline
Points: 162
|
Post Options
Thanks(0)
Quote Reply
Posted: April 13 2006 at 4:59pm |
Thank you so much! I'll be sure to send this on to him. And thanks for the communication suggestion Jon.
Sarah Lowry
|
|
Jared Wood
Guest
Joined: January 27 2004
Location: United States
Status: Offline
Points: 490
|
Post Options
Thanks(0)
Quote Reply
Posted: April 13 2006 at 5:55pm |
How does a Calcium Reactor work to effect:
- pH
- alkalinity
- calcium level
Does a calcium reactor completely replace dosing?
|
In the beginning, God created the heaven and the earth ... then He let it cycle. Have you read my dinosaur theory yet?
|
|
KeoDog
Guest
Joined: September 18 2002
Location: United States
Status: Offline
Points: 884
|
Post Options
Thanks(0)
Quote Reply
Posted: April 14 2006 at 7:32am |
|
Jon, I was told that PH will follow alkalinity. So if your alkalinity is in an exceptable range more than likely your ph will be as well. What is your opinion on this?
|
|
Kevin Kunz (Sandy, UT)
300g reef
"A trade by which one gains and the other loses is a fraud." Ayn Rand
|
|
jfinch
Guest
Joined: March 06 2003
Location: Pleasant Grove
Status: Offline
Points: 7067
|
Post Options
Thanks(0)
Quote Reply
Posted: April 14 2006 at 9:02am |
How does a Calcium Reactor work to effect:
- pH
- alkalinity
- calcium level
pH will tend to decline due to all the CO2. Alkalinity and calcium level should stay steady (thats the whole reason to have a reactor).
Does a calcium reactor completely replace dosing?
It can completely replace calcium and alkalinity dosing. Other stuff may or may not need dosing.
Jon, I was told that PH will follow alkalinity. So if your alkalinity is in an exceptable range more than likely your ph will be as well. What is your opinion on this?
It's generally true that a tank with a higher alkalinity will also have a higher pH, but really depends on the tank. But both alkalinity and dissolved CO2 effect saltwater pH. So if you have a tank with excessive amounts of CO2 (many tanks with calcium reactors and poor gas exchange or high indoor CO2 levels), you could have a high alkalinity and low pH. My tank runs with 3-3.5 meq/l alk but a pH of only 7.8 - 8.0 due to CO2.
|
|
|
|
chris.rogers
Guest
Joined: November 26 2005
Location: Washington DC
Status: Offline
Points: 1553
|
Post Options
Thanks(0)
Quote Reply
Posted: April 14 2006 at 9:44am |
Mme Lowry: http://www.advancedaquarist.com/issues/may2002/chem.htm Your question got me interested, I think that link would help. It comes from the advanced aquarist, so it must be true.
What are the tags to link it? [a href] doesn't work.
Edited by chris.rogers
|
|
Mike Savage
Guest
Joined: July 15 2005
Location: Murray
Status: Offline
Points: 19173
|
Post Options
Thanks(0)
Quote Reply
Posted: April 14 2006 at 9:48am |
|
|
|
|
|
smatney
Guest
Joined: July 08 2004
Location: United States
Status: Offline
Points: 1835
|
Post Options
Thanks(0)
Quote Reply
Posted: April 14 2006 at 12:39pm |
FYI - I was ready to duke it out about this as well. With my nursing background, I was sure that alkalinity was a pH measurement. Jon set me straight as well.
Thanks Jon for your expertise. You are loved.
|
|
Susan Matney
Farmington, UT
|
|
Lowry
Guest
Joined: March 04 2006
Location: Korea
Status: Offline
Points: 162
|
Post Options
Thanks(0)
Quote Reply
Posted: April 14 2006 at 1:10pm |
So...without a doubt you should be testing both pH AND alkalinity? I sent him the info Jon wrote but then he said he didn't see why we had to test for both. But you are saying it's possible to have one at a good level and one at a bad level at the same time? So testing both is necessary. Just want to finish clearing this up with the hubby. Thank you for all of your help.
Sarah Lowry
|
|
Adam Blundell
Presidency
Joined: June 24 2002
Location: Davis County
Status: Offline
Points: 18526
|
Post Options
Thanks(0)
Quote Reply
Posted: April 14 2006 at 1:23pm |
Yes, you need to test both. Most would agree testing alkalinity is more important. Unless you are running something unusual (ozone, CO2, etc) you won't have many changes in pH and really don't need to test it but every once in a while. Alkalinity is something you need to monitor, especially in reef aquariums.
I agree with Jon, anything said while in bed is either shrugged off or easily accepted.
Adam
|
|
Come to a meeting, they’re fun!
|
|
KeoDog
Guest
Joined: September 18 2002
Location: United States
Status: Offline
Points: 884
|
Post Options
Thanks(0)
Quote Reply
Posted: April 14 2006 at 2:03pm |
|
I havn't tested ph in about 2 yrs. I do test alkalinity about every 2 months. I probably would test ph if problems pointed that way.
|
|
Kevin Kunz (Sandy, UT)
300g reef
"A trade by which one gains and the other loses is a fraud." Ayn Rand
|
|
jfinch
Guest
Joined: March 06 2003
Location: Pleasant Grove
Status: Offline
Points: 7067
|
Post Options
Thanks(0)
Quote Reply
Posted: April 14 2006 at 2:22pm |
Absolutely, pH and alkalinty are two different animals.
pH = the amount of H+ ions floating around in the water
Alkalinity = the amount of CO3++ and HCO3+ floating around in the water
Monitoring and maintaining alkalinity is more of a concern then pH. My alkalinity can drop from 3.5 to 1.5 meq/l and only show a drop of about 0.1 pH units. Acros are severely stressed at an alkalinity of 1.5 meq/l.
|
|
|
|
amorgenegg
Guest
Joined: November 08 2005
Status: Offline
Points: 343
|
Post Options
Thanks(0)
Quote Reply
Posted: April 14 2006 at 2:28pm |
|
Doesn't alkalinity buffer the PH so that it doesn't change as easily as
with lower alkalinity? If it is buffering it and your PH doesn't
change as much, then it would not be as much of a stress to the animals
because the PH would be more stable. Is that right?
|
|
Andrew Morgenegg
|
|
jfinch
Guest
Joined: March 06 2003
Location: Pleasant Grove
Status: Offline
Points: 7067
|
Post Options
Thanks(0)
Quote Reply
Posted: April 14 2006 at 4:24pm |
amorgenegg, yes... but with some caveats.
|
|
|
|
chris.rogers
Guest
Joined: November 26 2005
Location: Washington DC
Status: Offline
Points: 1553
|
Post Options
Thanks(0)
Quote Reply
Posted: April 14 2006 at 11:38pm |
Which are? 
|
|
jfinch
Guest
Joined: March 06 2003
Location: Pleasant Grove
Status: Offline
Points: 7067
|
Post Options
Thanks(0)
Quote Reply
Posted: April 15 2006 at 12:08pm |
Really the only alkalinity that we are concerned about in our tanks is carbonate alkalinity. But others compounds also add to the alkalinity of our tanks such as borates. Borate is a much better buffer then carbonate... so if all you were worried about was a stable pH you could dump a bunch of borate into your tank, but don't do it 'cause it's not really a good idea .
|
|
|
|
