For high precision determination of the phosphate concentration
Phosphates (PO43–) are important nutrients for all plants and are vital for the energy metabolism of every living cell. Phosphates are released into the aquarium water via food and the decomposition process of organic matter. However, an unregulated increase in the phosphate concentration creates problems, such as significant algae growth. In addition, phosphates in salt water aquariums can seriously inhibit the deposition of calcium carbonate in the skeleton formation process of hard corals and, in turn, for their growth. On the other hand, there can be a shortage of phosphate if there is a high stock of plants and / or corals and a low fish population. In this situation, phosphate will need to be added. Some reef aquariums are intentionally set up to have ultra-low nutrient conditions – phosphate shortages can occur in cases such as these.
The phosphate concentration in natural saltwater is approximately 0.06 mg/l (ppm). However, the phosphate concentration in coral reefs may be much lower, typically between 0.01 and 0.02 mg/l (ppm). The objective is to establish an appropriate level in relation to the number and type of aquarium inhabitants. In freshwater applications, a phosphate concentration of up to 0.4 mg/l (ppm) is suitable; however 1 mg/l (ppm) should not be exceeded. Even a concentration of 0.02 mg/l (ppm) is adequate for supplying aquatic plants with nutrients. Therefore, the phosphate concentration in the aquarium water should be tested regularly.
With the high resolution Tropic Marin® Phosphate-Test Professional the phosphate concentration can be determined with a particularly high accuracy in the low concentration range between 0.01 and 1 mg/l.
• Measurement range: 0.01 – 1.0 mg/l (ppm) • Accuracy: 0.02 mg/l (ppm) • For determining the phosphate concentration in aquaria • Incl. comparator and phosphate standard to check function and shelf life of the test reagents • Sufficient for approximately 50 applications
How to use:
1. Shake the dropper bottles before use! Assemble and prepare the comparator. 2. Rinse out both glass cuvettes with tap water and then several times with aquarium water. 3. Fill each glass cuvette with exactly 15 ml of aquarium water using the dosing syringe. Put one of the two water samples aside as a reference. 4. Add 10 drops (for saltwater) or 12 drops (for freshwater) of test reagent A to the test cuvette, close the glass cuvette using the stopper and briefly shake the sample. 5. After that, add 3 drops of test reagent B, close the glass cuvette once again and briefly shake it. 6. After 4 minutes of development time place the open test cuvette and the reference cuvette with the water sample into the comparator. Place the comparator on the colour card in such a way that the reference cuvette is sitting on a coloured field and the test cuvette on a white field. 7. Now compare the opposing fields. To do this, look into the open cuvettes from above. Move the comparator on the colour card until both cuvettes match exactly. 8. Read off the phosphate concentration under the relevant colour field. If the colours do not match exactly, an intermediate value can be estimated. 9. Rinse out the glass cuvettes and the syringe thoroughly with tap water after the measurement process.
Using the “standard” to verify the test
The shelf life of reagents depends on storage conditions and other factors. If the functional capacity of the test is inadequate, there will be no colour reaction during the test, even if phosphate levels are particularly high. If the measurement result is below 0.1 mg/l (ppm), add three drops of the reference solution “standard” to a new sample in order to verify the reliability of the test. If the colour changes to blue when you carry out the test again, then the reagents are verified as good.
How to correct unfavourable values
If the phosphate concentration in the water is too high, we recommend:
• Using the highly efficient Tropic Marin® phosphate adsorbents: ELIMI-PHOS, ELIMI-PHOS Longlife or ELIMI-PHOS RAPID; • Assessing and, where necessary, reducing the stocking rate and feeding quantities or enriching the food with Tropic Marin® LIPOVIT / LIPO-GARLIC; • Removing detritus, dead plants and other dirt; • Stimulating the growth of organisms which consume nutrients, for example, more plants in freshwater tanks or more higher algae and corals in saltwater aquariums; • Using Tropic Marin® PRO-CORAL ORGANIC, NP-BACTO-BALANCE, NP-BACTO-PELLETS or other products to reduce the nutritional level in the medium term.
If phosphate levels are too low, we recommend (with due consideration for the nitrate concentration at the same time):
• Using PLUS-NP as a balanced source of nutrients in saltwater aquariums; • Increasing the feeding quantities;
Shelf life and storage6 months after opening. Store in a cool, dark place.
The entire instruction manual as PDF file can be found here: Phosphate-Test Professional
PO4-Test Professional 28350 Refill Pack 28786