NwT practical course 26.02.2007 (cold water aquarium/phosphorus compounds)

Measure of abiotic factors of the aquarium

Phosphorus compounds

measure the phosphorus concentration in the aquarium water:

material:

• 
  
  aquarium water


• 
  
  measure equipment to measure the phosphorus concentration, consisting of: a small test tube (6mm caliber and 3cm high), a test tube (1,5cm calibre and 5cm high), 2 phosphorus solution, control strips with a coloured comparison chart

experiment set up:

First we fill 5ml of the water into the bigger test tube and we add some drops of the first phosphorus solution. Now we shake the test tube to mix the water and phosphorus solution well. At the same time, some drops of the second solution are filled in the small test tube. Then we put a controlstrip for 15sec into the bigger test tube and then 15sec into the smaller one. Wait 2 minutes, then there will appear a colour to compare with the coloured comparison chart.

Result:

The colour that appeared was tuquoise. In this case, it means that the phosphorus concentration is 0mg/l.