Feed Circuit Blockages

The feed circuit, especially restrictive feed outlets like drippers, can become blocked with salt build-up, dirt, algae, root growth and medium.

To minimize this problem:

● Employ a filter on the inlet to the nutrient pump. Also, in recirculating systems, install a filter in the return line (Fig 2.6). Ensure filters have a large surface area. This will minimize how frequently they need to be cleaned.
● Position plants to avoid roots being drawn into drain outlets.
● Maintain nutrient pH well below 6.5 to help prevent precipitation.
● Routinely disinfect the nutrient solution to prevent the build-up of algae and slimes.
● Ensure nutrients are fully soluble.
● Avoid using water that has high “hardness” levels.
● Use stakes to secure the feed outlets above and away from the medium and roots to prevent them from becoming blocked.
● Where drippers or sprayers are used, allocate at least two per plant. Inspect and clean them regularly.
● Use a regular maintenance schedule. Routine 'discarding' and 'flushing' will help prevent the build-up of solids such as insoluble salts, algae and plant debris. Between crops it is useful to perform a chemical flush to remove insoluble precipitates.