Need help making calibration solutions - South Western Ohio Aquatic Plant Enthusiasts - Aquatic Plant Central

Go Back   Aquatic Plant Central > Local or Regional Clubs - (Click button on right to expand) > South Western Ohio Aquatic Plant Enthusiasts

South Western Ohio Aquatic Plant Enthusiasts A forum for the South Western Ohio Aquatic Plant Enthusiasts club.

Reply
 
LinkBack Thread Tools Display Modes
Old 10-24-2005, 02:56 AM   #1 (permalink)
Member
 
ElectricHead's Avatar
 
Join Date: Sep 2005
Location: Dayton,Ohio
Posts: 34
iTrader Ratings: 0
ElectricHead is a regular member
Default Need help making calibration solutions

I need a little help. I wish to make some calibration solutions to check my test kit for accuracy. The solutions I need to make are for KH and GH testing so I can determine Co2 levels. Tested my tap water yesterday and got a reading of GH of 23 degrees and a KH of 16 degrees and I just want to be sure about this.
ElectricHead is offline   Reply With Quote

Advertisement [Remove Advertisement]
Old 10-24-2005, 04:28 AM   #2 (permalink)
Senior Member
 
MatPat's Avatar
 
Join Date: Mar 2004
Location: Dayton, Ohio
Posts: 3,819
iTrader Ratings: 34
iTrader Positive Rating: 100%
MatPat is a valuable member of the community MatPat is a valuable member of the community
Default

According to the Fertilator above and Chuck's calculator:

3.5 gm of MgSo4 mixed in 5g of water will give you 18.2ppm of Mg. 1 gm of CaCl mixed in 5g of water will give you 19.08 ppm of Ca. Mix both in 5g of water and you should get about 2dGH (~37ppm).

You wouldneed about 1/4 tsp of Baking soda to raise the KH of 5g by 3dKH (~54ppm).

I have not done either of these tests in a small volume of water, but the KH seems to work for my 15g water changes. Please, let us know if they prove to be accurate.
MatPat is offline   Reply With Quote
Old 10-24-2005, 04:30 AM   #3 (permalink)
Senior Member
 
HeyPK's Avatar
 
Join Date: Jan 2004
Location: Soggy Central Mississippi
Posts: 4,696
iTrader Ratings: 25
iTrader Positive Rating: 100%
HeyPK is a valuable member of the community HeyPK is a valuable member of the community HeyPK is a valuable member of the community
Default

To calibrate for GH you would need to have a calcium chloride solution of known concentration. To calibrate for KH, you would use a sodium bicarbonate solution of known concentration. If you have access to laboratory equipment, a balance accurate to two or three places can be used to weigh the dry calcium chloride and sodium bicarbonate out. You would also need deionized or distilled water in which to dissolve these two substances. You might be able to buy standard test solutions from a chemical supply company or a company that makes test equipment. If your tap water is supplied by a water company, the company should be able to supply you with a water analysis that would give you the data you want. If you have your own well, you should be able to get your water analyzed. It might be easier, just to get a CO2 test kit.
HeyPK is offline   Reply With Quote
 
Old 10-24-2005, 04:58 AM   #4 (permalink)
NE
 
Join Date: Dec 2004
Posts: 162
iTrader Ratings: 0
NE is a regular member
Default

GH does not affect CO2 levels or vice versa normaly.

Kh tests are usually quite accurate, if you like to make more exact measurement double, triple or quadruple the water amount, then the number of drops are parts of degrees instead.

double = 0,5 degrees / drop
triple = 0,33 degrees / drop
quadruple = 0,25 degrees /drop
NE is offline   Reply With Quote
Old 01-29-2006, 08:33 PM   #5 (permalink)
Senior Member
 
dennis's Avatar
 
Join Date: Mar 2004
Location: Leverett, Mass
Posts: 2,988
iTrader Ratings: 47
iTrader Positive Rating: 100%
dennis is a regular member
Default

Time to bring this back to life as I need to calibrate my test kits....

From the krib, http://www.thekrib.com/Plants/CO2/ha...arryfrank.html

Quote:
By definition, 1dGH = 10 mg/liter CaO
Atomic Weight Ca = 40, O = 16, CaO = 56
So 10 mg/liter CaO contains 40/56 *10 = 7.143 mg/liter of Ca
By definition ppm Ca is not for elemental calcium but for ppm CaCO3.
Atomic weight CaCO3 = 100
So 7.143 mg/liter of elemental Ca would be expressed as 100/40 * 7.143 = 17.8575 mg/liter(ppm)CaCO3.
1dGH = 17.86 ppm CaCO3 and 7.143 ppm Ca2+.

I want to make a GH test sample using 1 gallon of DI water. According to the Fertilator, adding .5grams CaCl2+2H2O yields 36.1mg/l Ca. Divide 36.1/7.143=5.05 degree GH. Is this correct?


Using baking soda, NaHCO3, to adjust kH:
Info below from the same source as above:
Quote:
1dKH = 21.8 ppm HCO3
How to use these conversion factors:
If you have alkalinity in ppm or hardness in ppm divide by 17.86 to get degrees.
If you want to raise the alkalinity by 1dKH using CaCO3: use 17.86 mg CaCO3
If you want to raise the alkalinity by 1dKH using NaHCO3:
mw Na = 23
mw HCO3= 61
mw NaHCO3= 84
1dKH= 21.8 ppm HCO3
21.8 *84/61=30 mg/liter of NaHCO3
using molarity:
0.358 mMoles * 84(mwNaHCO3) = 30 mg/liter of NaHCO3



Unfortunately I do not know how to interperate that. I would like to add NaHCO3 to 1 gallon of DI to make my test solution. If necessary I can make the gallon with a high kH then dilute that sample as necessary for easy measurment. I have graduated cylinders and syringes so dealing with measurment accurately is easy enough. I also have a gram scale with a 0.1 readout.


Would it be possible to use the same gallon of DI for both tests? The CaCl2+2H2O should not affect the kH but would the NaHCO3 have an effect on the GH reading?

Last edited by dennis; 01-29-2006 at 08:36 PM..
dennis is offline   Reply With Quote
Old 01-31-2006, 03:17 PM   #6 (permalink)
Senior Member
 
dennis's Avatar
 
Join Date: Mar 2004
Location: Leverett, Mass
Posts: 2,988
iTrader Ratings: 47
iTrader Positive Rating: 100%
dennis is a regular member
Default

Could anyone help me check that math. I am pretty sure it is wrong but I don't know.

I'd really appreciate it
dennis is offline   Reply With Quote
Reply


Aquatic Plant Central > Local or Regional Clubs - (Click button on right to expand) > South Western Ohio Aquatic Plant Enthusiasts > Need help making calibration solutions

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Aquatic Plant Forum Replies Last Post
JBJ Regulator/Solenoid making noise omega Equipment 5 07-25-2006 05:51 AM
Making a black backround in Photoshop niko Photography 11 10-18-2005 01:52 PM
pH Controller Calibration Jim Equipment 4 04-30-2005 01:49 PM
Making red plants red & keeping spot algae away overdrive Algae 9 12-12-2004 07:07 PM


All times are GMT -8. The time now is 04:06 AM.

Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2020, vBulletin Solutions, Inc.

Search Engine Friendly URLs by vBSEO 3.6.1