And We're BACK!
Hey, everybody!
Sorry for the week of silence — our school was on Thanksgiving Break, and while we were all catching up on sleep and enjoying some turkey and pie, our experiment was running at school.
Just to refresh your memory, our experiment involves making the pH of one water supply more acidic than the pH of the other water supply and seeing how it would affect the growth (i.e. number of leaves, vine height, etc.) of the peas.
The day before Thanksgiving Break, I got to work (with our teacher's help) figuring out a way to adjust the pH. Initially, we thought that adding coffee grounds would boost the acidity, but then we had a lightbulb moment — citric acid! I juiced a lime and, using a pH probe to get an accurate reading of the water's pH, slowly added it to Tower 2, the Tower whose pH we were adjusting. Both reservoirs had ample amounts of nutrients, a solution that maintained a fairly neutral pH (anywhere along the 7 scale) and kept the plants healthy. By adding lime juice, the pH was reduced to somewhere between 5.5 and 6.0, much more acidic than what the peas needed to stay happy and healthy.
We returned from break yesterday and saw what we had expected (and hoped!) to see:
Tower 2's inhabitants had dried out and shriveled up, though whether from the acidic solution or the low water pressure is unclear — the water had ceased bubbling up the tube of the structure because there wasn't enough downwards force to push it upwards, but we have no way of knowing how long the water ran before it stopped. Regardless, Tower 2 is no more, though we adjusted the nutrient and water levels to get it working smoothly again.
Tower 1's inhabitants were thriving. Plants 4 and 5 were doing better than 6, who had been kind of squished against the side of its bottle by the end of the lift tube — I trimmed the tube so 6 had more room to grow. It seems that our tower works perfectly, even over longer periods of time, and over the next week, we'll continue to run our experiment, measure variables, and hopefully see a lot more plant growth.
Keep up with us on our instagram and twitter for more updates :)
Our proud Pea #5:
- Emily








