FILL CONTAINER WITH WATER

Fill a clean container, such as a bucket, with a measured quantity of water. If you are using tap water, it is recommended that you leave it to stand for up to 24 hours, so that it can settle to room temperature. This will also allow some of the chlorine in the water to evaporate off.

ADDING NUTRIENT CONCENTRATE

‘ONE PART’ NUTRIENT CONCENTRATE

If you are using a ‘one part’ nutrient concentrate, this should be added according to the manufacturers instructions. This is usually 5 — 10 mis of concentrate to 1 litre of water.

ADDING NUTRIENT CONCENTRATE

‘TWO PART’ NUTRIENT CONCENTRATE

When using a ‘two part’ nutrient concentrate , if the instructions recommend using 5 mis per litre, add 5 mis each of both part A and part B (10 mis in total). Add the two parts to the water separately, as they will precipitate if mixed together.

ADDING NUTRIENT ADDITIVES

If you are using any nutrient additives then they should be added at this stage.

MEASURING PH

You will now need to test the pH level of the solution, using either an electronic meter or a liquid pH test
kit.

USING A LIQUID PH TEST KIT.

Different test kits operate slightly differently so always follow the manufacturers instructions. However, they all follow a similar procedure.

Take a measured sample of the nutrient solution (usually only a few mis are required).

Add a measured amount of re-agent (usually only a few drops)

The sample will then change colour (somewhere between orange and blue). By comparing this to the test strip provided the pH level can be judged. If you are using tap water this should be between 5.0 — 8.5.

CORRECTING THE PH LEVEL

As explained previously, the pH level will probably need correcting. PH solution (either ‘up’ or ‘down’) is added drop by drop until the desired pH level of 6.00 is reached. Initially you may have to do several retests until the pH level is correct, but with experience this becomes easy and you will soon be able to tell the pH level by the colour and know how much pH solution to add to correct it.

You now have a ‘working solution’ which can be added to the system.