Aquaponics in Action
We recently worked on the concept of fair test in stage four, and to explore the concept fully we conducted what was in essence a fair test that involved controlling the variables that affect the germination of seeds. Towards the end of the experiment we had a number of containers with all sorts of seedlings in them that appeared to be doomed to wither and die in their containers.
As happens every year a handful of students wanted to ‘save’ the seedlings somehow but, as usual, did not have a clear idea as to how to do it. It was here that the thought occurred to me that a small aquaponics system in the classroom could be used to not only ‘save’ a number of the poor doomed seedlings, but to further explore the conditions seeds need to germinate and grow into thriving plants.
I had a small aquarium which I had bought from lifeline and had repaired, so the ‘pond’ part of my aquaponics system was solved now I needed a grow bed to act as a bio filter and to give the plants a place to grow. I sourced all the material from the maintenance department of our school (I basically carted off almost all their off cuts and scrap material). I made a grow bed equal in volume as the tank so as to allow for both small and large populations of fish. As it was to be a display piece in the classroom it received a much-needed coat of paint as well.
I set the system up early on morning so that by the time the students came into class it was running, which got them asking a lot of questions and we landed up using several home group sessions discussing how such a system works and the benefits of such a system.
As the aquarium is only stocked with one redclaw it has not been able to provide enough nutrients in the water for the growing seedlings. I was pleasantly surprised when a small group of my students asked what was wrong with the plants as they were not growing very fast or very well (apparently they had been watching the system closer than I had thought). We discussed the need to a higher population of fish in order to properly feed our scrawny seedlings. They in turn took it upon themselves to raise the money we needed to purchase a number of goldfish, which we will do at the start of term 4.
The little aquaponics system in my classroom has been an item of much discussion and seems to have sparked the interest of more children than I had anticipated. In all it has been much more of a success than I had hoped for and will be a part of my class for a long time to come.
Peace Lutheran College