Fishtank (4)

Article no. 4 about the fishtank, november 16, 2019.

First about the status of the control at the moment. As already mentioned in previous articles, the adding of osmose water to compensate the evaporized water is made and now also the replacement of a percentage of the salt water (once every 2 weeks) is added to the control.

The next part of the project is testing the sensors for the waterlevel, pH and TDS (OPS, redox to come in the future). The water levels are important for signaling the level in the tank (for monitoring), the sump (evaporation and replacing salt water) and the osmose tank. I want to analyze the stability and test how robust these sensors are over time. pH and TDS are now tested for a week and the test for the level sensor is started today. pH is important for monitoring the quality of the water and the TDS is important for testing the quality of the osmose installation.

The following sensors are tested:

  • pH, PH-4502C
  • TDS, Analoge TDS sensor
  • Level, MPX5010DP 0-10KPa (~0..100cm) water column

See the photos below for the test setup:

Test setup ft4   

On the foreground the TDS sensor, pH and in the box -filled with water- the levelsensor.


Recordings (mp4 video)

  • Recording of scada with the new sensors (click on this link). Remark: recording starts in the proces of replacing an amount of salt water in the system (state SALTWATER-TO-DRAIN). There is already salt water made in the osmose tank and will be transported to the sump at about 1:00 minute in the recording.
  • Recording of the penplotter with pH, TDS and level sensor (click on this link)