TEST KIT
Hydroponics
MODEL AM-41
CODE 5406
TA BLE OF CON TENTS
WARNING! This set contains chemicals
that may be harmful if misused. Read
cautions on individual containers
carefully. Not to be used by children
except under adult supervision
Page
Contents List .................................................................................4
Dilution Procedure .........................................................................6
Test Procedures:
pH....................................................................................................6
Nitrate Nitrogen..............................................................................7
Phosphorus.......................................................................................7
Potassium.........................................................................................7
Ammonia Nitrogen .........................................................................8
Sulfate..............................................................................................8
Iron ..................................................................................................9
Calcium and Magnesium.................................................................9
Plant Tissue Testing .....................................................................11
Chemistry of the Test Reactions...................................................12
3
CON TENTS LIST
QUANTITY CONTENTS CODE
30 mL Ammonia Nitrogen Reagent #1 4797WT-G
30 mL *Ammonia Nitrogen Reagent #2 *4798WT-G
10 g *Nitrate Reducing Reagent *V-6279-D
2 x 60 mL *Mixed Acid Reagent *V-6278-H
50 *Sulfate Turb Tablets *6456-H
15 mL *Inhibitor Solution *9258-E
15 mL *TEA Reagent *3921-E
30 mL Calcium-Magnesium Inhibitor Reagent 3922-G
30 mL *Sodium Hydroxide Reagent
*4259-G
w/Metal Inhibitors
100 Calcium Hardness Indicator Tablets T-5250-J
30 mL *Calcium & Magnesium Buffer *5126-G
30 mL *CM Indicator Reagent *6522WT-G
60 mL Standard EDTA Reagent 5254-H
60 mL *Hydrochloric Acid, 1.0N *6130WT-H
30 mL *Sodium Hydroxide, 1.0N *4004WT-G
60 mL *Hydroculture pH Indicator *5132-H
60 mL *Hydroculture VM Phosphorus Reagent *5138-H
30 mL Charcoal Suspension 5638-G
30 mL *Ferric Iron Test Solution *5116PS-G
10 g *Iron Reagent Powder *5275-D
250 mL Deionized Water 5115PT-K
5 g *Tetraphenylboron Powder *6364-C
6 Test Tubes, 5 mL, glass, w/caps 0230
1 Graduated Cylinder, 10 mL, glass 0416
1 Spoon, 0.1 g, plastic 0699
2 Test Tubes, 5 & 10 mL, glass, w/caps 0820
2 Test Tubes, 10 mL, glass, w/caps 0822
1 Pipet, glass, w/cap 0341
1 Direct Reading Titrator, 0-500 Range 0383
1 Test Tube, 5.2 mL, glass, w/cap 0645
1 Pipet, 1.0 mL, plastic 0354
4
QUANTITY CONTENTS CODE
4 Test Tubes, 5-10-12.9-20-25 mL,
0608
glass, w/caps
1 Filter Paper 0465
2 Funnels, plastic 0459
2 Pipets, plain, plastic 0352
2 Spoons, 0.05 g, plastic 0696
1 Spot Plate, plastic 0159
1 Tablet Crusher 0175
1 Double Tube, Potassium, w/cap 0780
1 Brush, test tube 0514
1 Ammonia Nitrogen Comparator, 1-8 ppm 4796
1 Nitrate-N Comparator, 0.25-10 ppm 3109
1 Sulfate Comparator, 0-200 ppm 7779
1 Hydroculture pH Comparator, 4.8-7.6 5304
1 Phosphorus Comparator, 3-30 ppm 5305
1 Plant Nutrition Studies 1596
2 Dispenser Cap 0692
*WARNING: Reagents marked with a * are considered to be potential
health hazards. To view or print a Material Safety Data Sheet (MSDS) for
these reagents see MSDS CD or www.lamotte.com. To obtain a printed
copy, contact LaMotte by email, phone or fax.
To order refill reagents or test kit components, use the specified code
numbers.
Read the LaMotte Direct Reading Titrator Manual and the Octet
Comparator Manual before proceeding.
5
DI LU TION PRO CE DURE
If the test result in the nitrate, phosphate, potassium, ammonia nitrogen or
sulfate test is greater than the highest comparator value it is necessary to
perform a dilution. Dilutions are made with Deionized Water (5115PT).
Amount of Sample Dilute To Multiply Result By
1.0 mL 2.0 mL 2
1.0 mL 5.0 mL 5
1.0 mL 10.0 mL 10
1.0 mL 20.0 mL 20
1.0 mL 25.0 mL 25
TEST PRO CE DURES
pH
A pH value of 7.0 indicates a neutral solution. Values above 7.0 indicate
alkaline solutions, while values below pH 7.0 indicate acid solutions.
1. Fill test tube (0230) to 5 mL line with the sample.
2. Add 10 drops of *Hydroculture pH Indicator
(5132). Cap and mix.
3. Insert test tube into the Hydroculture pH
Comparator (5304). Match sample color to a
color standard. Record as pH.
NOTE: If the pH of the sample is not
between 6.2 and 6.8, it must be adjusted to 6.5
before proceeding with the following tests. If
the pH is below 6.2 add *Sodium Hydroxide,
1.0N (4004WT), one drop at a time,
periodically checking the pH until it is
brought into the range of 6.2 to 6.8. If the pH
is above 6.8, add *Hydrochloric Acid, 1.0N
(6130WT) in the same manner.
6
NITRATE NITROGEN
The Nitrate Nitrogen Comparator measures levels from 0.25 to 10 ppm.
Most nutrient solutions will have to be diluted to bring them into this
range. A 1 to 20 dilution is suggested (see Page 6).
NOTE: Place Dispenser Cap (0692) on *Mixed Acid Reagent (V-6278).
Save this cap for refill reagents.
1. Fill test tube (0820) to the first line with the sample.
2. Dilute to second line with *Mixed Acid Reagent (V-6278). Cap and
mix. Wait two minutes.
3. Use the 0.1 g spoon (0699) to add one level measure (avoid any
excess) of *Nitrate Reducing Reagent (V-6279). Cap and invert the
tube 50-60 times in one minute. Wait 10 minutes.
4. Insert test tube into the Nitrate-N Comparator (3109). Match sample
color to a color standard. Record as ppm Nitrate Nitrogen.
If the original sample was diluted, multiply the reading by 20. Record
as ppm Nitrate Nitrogen.
PHOSPHORUS
The Phosphorus Comparator measures levels from 3 to 30 ppm. Most
nutrient solutions will have to be diluted to bring them into this range. A
1 to 2 dilution is suggested (see Page 6).
1. Fill test tube (0230) to the line with sample.
2. Use the 1.0 mL pipet (0354) to add 1.0 mL of *Hydroculture VM
Phosphorus Reagent (5138). Cap and mix. Wait 5 minutes.
3. Insert test tube into the Phosphorus Comparator (5305). Match
sample color to a color standard. Record as ppm Phosphorus.
If the sample was diluted, multiply the reading by 2. Record as ppm
Phosphorus.
POTASSIUM
A turbidimetric method is used for the determination of potassium in the
nutrient solution. It is suggested that the nutrient solution be diluted to a 1
to 5 ratio with deionized water to bring the sample concentration within
the range of the test. A 1 to 5 dilution involves diluting 2 mL of the
sample to 10 mL with Deionized Water (5115PT).
1. Remove the square inner tube and collar.
2. Fill the round tube to the first line (8 mL) with the diluted sample.
3. Dilute to the second line with Deionized Water (5115PT).
4. Add 2 drops of *Sodium Hydroxide Reagent w/Metal Inhibitors
(4259). Cap and mix.
7
5. Use the 0.05 g spoon (0696) to add one level measure of
*Tetraphenylboron Powder (6364). Cap and shake vigorously for 30
seconds until all the powder has dissolved. A white precipitate will
form immediately. Allow the tube to stand for 5 minutes.
6. Shake the tube again. Remove cap and slowly insert the square tube
with the collar. The square tube will slide up and down through the
collar and will fill with liquid.
Viewing from above, adjust the square tube into the turbid solution
until the black dot on its base just disappears. Hold the round tube at
the top to avoid blocking light.
7. Read result where liquid meets scale. Record as ppm Potassium. If
sample was diluted, multiply by 5. Record as ppm Potassium.
NOTE: Brush tubes thoroughly after each use.
AMMONIA NITROGEN
The Ammonia Nitrogen Comparator measures levels from 1 to 8 ppm.
Most nutrient solutions will have to be diluted to bring them into this
range. A 1 to 20 dilution is suggested (see Page 6).
1. Fill test tube (0230) to 5 mL line with sample.
2. Add 4 drops of Ammonia Nitrogen Reagent #1 (4797WT). Cap and
mix.
3. Add 8 drops of *Ammonia Nitrogen Reagent #2 (4798WT). Cap and
mix.
4. Insert test tube into the Ammonia Nitrogen Comparator (4796).
Match sample color to a color standard. Record as ppm Ammonia
Nitrogen.
If sample was diluted, multiply by 20. Record as ppm Ammonia
Nitrogen.
SULFATE
The Sulfate Comparator measures levels from 0 to 200 ppm. Most nutrient
solutions will have to be diluted to bring them into this range (see Page 6).
1. Fill test tube (0822) to line with sample.
2. Add one *Sulfate Tur b Tablet (6456). Cap and shake vigorously for at
least one minute to dissolve the tablet.
8
3. Immediately insert test tube into the Sulfate Comparator (7779).
Match the sharpness of the lines behind the sample to the sharpness of
lines behind the standard. Record as ppm Sulfate.
NOTE: Disregard any difference in color between the test sample and
standards.
NOTE: Thoroughly rinse and clean test tubes after each test.
IRON
A special spot test method detects low concentrations of iron that are
present in the nutrient solutions. No dilutions are required, but it is
suggested that a blank be used as a means of comparison with the test
sample. The limit of detection is 0.25 ppm.
1. Use pipet (0352) to add 4 drops of sample to a depression on the spot
plate (0159).
2. Use the 0.05 g spoon (0696) to add one measure of *Iron Reagent
Powder (5275). Mix with the stirring rod (0519).
3. Add 2 drops of *Ferric Iron Test Solution (5116PS). Use tablet
crusher (0175) to stir solution thoroughly. Solution will immediately
turn red or pink if iron is present.
CALCIUM AND MAGNESIUM
The Schwarzenbach EDTA titration method, used to determine calcium
and magnesium, involves two titrations. The first gives the combined
calcium and magnesium content and the second gives only the calcium
content. Magnesium is calculated from the difference between the two
titration values.
Read the Direct Reading Titrator Instruction Manual before proceeding.
TI TRA TION A, CAL CIUM AND MAG NE SIUM
1. Fill the test tube (0645) to the line with the nutrient solution.
2. Add 5 drops of Calcium-Magnesium Inhibitor Reagent (3922). Swirl
to mix. Wait 5 minutes.
3. Add 5 drops of *Calcium & Magnesium Buffer (5126). Swirl to mix.
4. Add 10 drops of *CM Indicator Reagent (6522WT). Swirl to mix.
Solution will turn red.
9
5. Fill the Direct Reading Titrator (0383) with Standard EDTA Reagent
(5254). Insert Titrator tip into the center hole of the titration tube
cap.
6. While gently swirling the tube, slowly press the plunger to titrate until
the color changes from red to blue.
7. Read the result where the plunger tip meets the scale. Record as
Value A.
TI TRA TION B, CAL CIUM
1. Fill the test tube (0645) to the line with nutrient solution.
2. Add 2 drops of *Inhibitor Solution (9258). Swirl to mix.
3. Add 2 drops of *TEA Reagent (3921). Swirl to mix.
4. Add 8 drops of *Sodium Hydroxide Reagent w/Metal Inhibitors
(4259). Swirl to mix.
5. Add one Calcium Hardness Indicator Tablet (T-5250). Cap and shake
until tablet disintegrates. Solution will turn red.
6. Fill the Direct Reading Titrator (0383) with Standard EDTA Reagent
(5254). Insert Titrator tip into center hole of test tube cap.
7. While gently swirling the tube, slowly press the plunger to titrate until
the red color changes to a clear blue which lasts for at least one
minute.
8. Read the result where the plunger tip meets the scale. Record as
Value B.
FI NAL RE SULTS
Calcium Content = 0.4 x Titration Value B = ppm Ca
Magnesium Content = 0.24 (Value A – Value B) = ppm Mg
EX AM PLE:
Titration Value A is 480 ppm CaCO
Titration Value B is 400 ppm CaCO
3
3
Calcium = 0.4 x 400 = 160 ppm Ca
Magnesium = 0.24 x (480 – 400) = 0.24 x 80 = 19.2 ppm Mg
10
PLANT TIS SUE TESTING
As a supplement to the nutrient solution tests provided in this kit,
additional tests can be conducted on fresh plant tissue, or an extract of the
fresh plant tissue. These tests frequently allow verification of suspected
nutrient deficiency or other abnormalities.
Fresh plant material should be obtained from the growing plants, both
normal and questionable plants. It is important to test healthy plants at the
same time that the tests are made on questionable plants, as the greatest
value may be derived from the tests when they are used in a comparative
manner. If plant parts are to be used, select small lots of leaf petioles, or
succulent portions of the stem, in the plant part most affected by any
observable symptom. Using a clean, sharp knife or razor blade, cut the
material into fine bits of not more than to inch in length and thickness.
Use equal weights of plant material from health and unhealthy plants. A
weighed sample is necessary because there is variation in the size of plant
material used in the tissue analysis.
Algae cells may also be used for tissue analysis. Equal amounts of algae are
filtered or centrifuged from the nutrient solution. The cells are ground up
by the use of a glass homogenizer, weighed and put in the extraction tube.
1. Fill two test tubes (0608) to the 5 mL line with the weighed plant
tissue.
2. Dilute to 20 mL with Deionized Water (5115PT). Cap and shake
vigorously for 5 minutes.
3. Use the funnels (0459) and filter paper (0465) filter the tissue extract
into clean test tubes (0608).
NOTE: If excess turbidity or color is found in the extract add 3 drops
of Charcoal Suspension (5638) to the extraction tube. Shake for 1
minute and refilter.
5. Test filtrate following the same procedure used to test a nutrient
solution for a particular nutrient. The tissue extract is substituted by
volume for the nutrient solution or an appropriate dilution of the
nutrient solution.
DISCUSSION OF RESULTS: The results should be interpreted on a
comparative basis. No definite values can be assigned for general
application, since the magnitude of the results obtained on different species
and under different growing conditions may vary significantly.
Interpretations should be based on comparisons of the same species and
age, and grown under the same general cultural conditions.
11
THE CHEM IS TRY OF THE TEST RE AC TIONS
The following information pertains to the nature of the chemical tests used
in this kit. Although the information is not totally complete, it does
provide the teacher or student with the basic chemistry of the reagents and
a description of the reactions as they are thought to occur.
CALCIUM-MAGNESIUM
*Calcium & Magnesium Buffer Ammonia Buffer *5126
*TEA Reagent Triethanolamine *3921
*CM Indicator Eriochrome/Triethanolamine *6522
Standard EDTA Reagent Disodium Salt EDTA 5254
*Sodium Hydroxide Reagent Sodium Hydroxide *4259
Calcium Hardness Indicator Tablets Calcon 5250
Calcium-Magnesium Inhibitor
Reagent
*Inhibitor Solution Sodium Sulfide *9258
Ethylenediaminetetraacetic acid (EDTA) and its disodium salts form
chelate complexes with metal cations. Calcium and magnesium complexes
are colorless and the calcium-EDTA complex is more stable than the
magnesium-EDTA complex.
The Eriochrome dye also forms complexes with calcium and magnesium;
the magnesium-dye complex is more stable than the calcium-dye complex.
In the pH range from 8.5 to 11.5 an aqueous solution of the dye is blue,
while it’s calcium and magnesium complexes are red. The Calcium &
Magnesium Buffer is added to bring the sample within this pH range.
CDTA is used to complex or mask interfering metals.
If EDTA titrant is added the calcium, and then the magnesium is extracted
from their dye complexes. After sufficient EDTA is added to complex all of
the magnesium as well as the calcium, the solution will turn blue.
CAL CIUM
At a pH of about 12, Calcon indicator forms a red complex with calcium.
A sodium hydroxide solution is required to bring the pH within the desired
range. The sodium sulfide and TEA are used to complex or mask
interfering metals. EDTA combines with calcium before it combines with
magnesium and is capable of extracting calcium from the Calcon complex
and thus, restores the blue color of Calcon. Magnesium does not change
the color of Calcon at this pH.
CDTA 3922
12
SULFATE
*Sulfate Tu rb Tablets *6456
The single tablet reduces the pH and precipitates sulfate as barium sulfate
(BaSO4). The sulfate level in ppm is determined turbidimetrically.
IRON
*Ferric Iron Test Solution KCNS (thiocyanate) *5116PS
*Iron Reagent Powder Sulfamic Acid *5275
Ferric (Fe+3) ions react with the thiocyanate ions in an acid solution to
yield a red or pink color which is ferric thiocyanate.
NITRATE
*Mixed Acid Reagent Acid Salt Solution *V-6278
*Nitrate Reducing Reagent Cadmium Reduction Mixture *V-6279
The Nitrate (NO3) is reduced to the Nitrite (NO2) by the cadmium
reagent and forms nitrous acid with the salt solution. The nitrous acid
produces a red dyestuff through a diazotization process.
AMMONIA
Ammonia Nitrogen
Reagent #1
*Ammonia Nitrogen
Reagent #2
Ammonia Reagent #1 is added to prevent precipitation of residual calcium
and magnesium ions in the presence of the alkaline Nessler’s Reagent.
*Ammonia Reagent #2 is then added to the sample. If ammonia is present
a yellow color is developed which is probably oxidimercuric ammonium
iodine (NH2Hg20I).
Stabilizer-Rochelle Salt
(potassium and sodium
tartrate-APHA Solution)
Nessler’s Reagent
(anhydrous mercuric iodide,
anhydrous potassium iodide, and
Nessler’s Reagent [anhydrous
mercuric iodide, anhydrous
potassium iodide, and sodium
hydroxide])
13
4797WT
*4798WT
pH
*Hydroculture pH Indicator
Solution
The pH indicator is a mixture of organic dyes that exhibit different colors a
various pH levels.
PHOSPHORUS
*Hydroculture VM
Phosphorus Reagent
The inorganic phosphate reacts with the molybdate solution to form a
yellow phospho-molybdate compound.
POTASSIUM
*Tetraphenylboron Powder Sodium Textraphenylborate *6364
*Sodium Hydroxide Reagent Sodium Hydroxide *4259WT
A solution is made alkaline with sodium hydroxide. Potassium combines
with sodium tetraphenylborate to form potassium tetraphenylborate which
precipitates and causes the solution to become cloudy.
Methyl Red, Bromthymol Blue
in 95% alcohol
Ammonium Vanadate Molybdate
in Sulfuric Acid Solution
*5132
*5138
14
LaMOTTE COM PANY
Helping Peo ple Solve An a lyt i cal Chal lenges
PO Box 329 • Chestertown • Mary land • 21620 •USA
800-344-3100 • 410-778-3100 (Out side U.S.A.) • Fax 410-778-6394
Visit us on the web at www.lamotte.com
®
03/11
Loading...