Tropic Marin K+ Pro Potassium Test Professional

Potassium Test Professional by Tropic Marin is a test for checking the potassium content in saltwater aquariums. The necessary test cuvettes, reagents and dosing syringes are included in the set. The test kit also contains a potassium standard to check the functionality of the test. The reagents can be bought as refill packs after they have been used up.

Potassium in saltwater aquariums

Potassium is an important alkali metal and micronutrient that is essential for all living beings including marine organisms. Therefore, potassium concentrations in aquarium water must be checked regularly and adjusted as necessary. If potassium is not present in sufficient amounts, potassium deficiencies can occur. This can cause discolouration in corals.

Natural seawater contains a potassium concentration of 408 mg/L. In a saltwater aquarium, the optimal value is between 380 and 420 mg/L.

Instructions for use:

To get a more precise measurement, determine the correction value with the potassium standard first. This value must then be taken into account for each subsequent potassium measurement. The manufacturer recommends determining the correction value every 3-4 weeks.

1 Determining the correction value:

1. Shake all reagent bottles before use.
2. Place the tip of a clean dosing syringe with the green plunger and draw up 1 ml of potassium standard. Pour this into one of the cuvettes.
3. Now carry out the potassium measurement (below).
4. Determine the correction value using the table in the instructions for use. To do so, get the corresponding potassium concentration of the residual amount of Reagent D on the table. Subtract this value from the standard value of 400 mg/L. This will give you the potassium correction value K.

Example:

Residual amount of reagent D: 0.44 ml
Potassium concentration (from the table): 410 mg/L

Calculation: 400 mg/l - 410 mg/l = - 10 mg/L

5. Rinse all measuring devices and cuvettes thoroughly after each use!

2 Determining the potassium concentration:

1. Shake all reagent bottles before use.
2. Attach a clean syringe tip to the 1 ml dosing syringe with the green plunger. Rinse the syringe a few times with the aquarium water to be tested. Draw up 1 ml of the water. Pour the contents into the empty cuvette.
3. Place a clean tip on the 1 ml dosing syringe with red lettering and draw up reagent A to the 20 mark (corresponds to approx. 0.5 ml). Add the entire contents to the water sample.
4. Swirl the cuvette with the water sample for about 10 seconds so that the reagent mixes well. Let the cuvette rest for 5 minutes. It should turn cloudy (white).
5. Add 9 drops of Reagent B, swirl the cuvette for 19 seconds, and then let it sit for 2 minutes.
6. Add 3 drops of Reagent C from the dropper bottle. The water sample turns yellow.
7. Put a clean tip on the 1 ml dosing syringe with black lettering and use it to draw up 1 ml of Reagent D. Add 3 drops of Reagent D to the water sample. Add drop by drop and not all at once! Mix the reagents by gently shaking the cuvette. Continue until the yellow colour fades to pale pink.
8. After dripping and swirling, a rich pink colour should emerge. Now read the remaining amount of reagent D in the syringe.
9. If you want to determine the correction value, then refer to point 1.4. You can carry out the potassium measurement of your water sample (without the correction value) in the next step.
10. After you have determined the remaining amount of reagent D, you can read the potassium concentration from the table in the instructions for use.
11. Clean the syringes and syringe tips with reverse osmosis water and let them dry thoroughly. After the measurement, rinse the glass cuvettes with tap water. You can clean the cuvettes with kitchen paper, then rinse them with reverse osmosis water and let them dry.

Contents:

• 1 x 12 ml potassium standard (400 mg/l)
• 1 x 25mL Reagent A
• 1 x 25mL Reagent B
• 1 x 5mL Reagent C
• 1 x 30mL Reagent D
• 2 x 10ml glass cuvettes
• 3 x dosing syringes 1 ml with attachment
• 1 x instruction manual

Our expert Oliver Knott recommends:

Along with nitrogen and phosphorus, potassium is one of the main nutrient elements for plants. If there are defects, the aquarium plants cannot develop properly!