To four of our goldfish: rest in peace.
Three died over the MLK holiday, most likely due to underfeeding.
We also noticed that one of our fish was partially cannibalized (which supports our above possible explanation).
The fourth one died today, of causes later discussed in this post.
Lots of questions have been asked by some of our readers of the previous aquaponics post. We'll answer them here.
A revised hypothesis:
If a deep water culture aquaponics system is arranged to grow basil (Ocimum basilicum), parsley (Petrosilenium crispum), and other similar leafy plants, then the plants in the aquaponics system will grow faster and larger than plants in a regular soil bed.
From Our Literature Review:
“Again, it [Deep Water Culture] is better suited to growing herbs and leafy green vegetables than plants with bigger root systems and fruiting varieties.”
"Different Types of Aquaponics Systems." Different Types of Aquaponics Systems. Aquaponics and You, n.d. Web. 06 Dec. 2015. <http://www.aquaponicsandyou.com/aquaponics-systems/different-types-of-aquaponics-systems/>.
“We have found that the aquaponic plants grow and produce faster in the system than in a traditional garden.”
"Aquaponics How To." : Aquaponics Plants. Aquaponics HowTo, 2016. Web. 21 Jan. 2016. <http://www.aquaponicshowto.com/aquaponics-plants/overview/22/>.
“Rakocy et al. [9] developed commercial-scale aquaponics systems that have been raised Basil, lettuce, okra and other crops successfully with outstanding quality and yields.”
Roy, M., Salam, M.A., Hossain, M.B., & Shamsuddin, M. (2013). Feasibility Study of Aquaponics in Polyculture Pond. World Applied Sciences Journal, 23. 588-592. doi: 10.5829/idosi.wasj.2013.23.05.74168
Our Independent Variable:
Amount of water given to plants in both types of cultivation
Dependent Variables:
Plant height (cm)
Plant mass (grams)
Plant photosynthetic rate (mL water used/s)
Controls:
Hours of light received by plants
Temperature plants are kept at
Nutrients in the soil
Experimental Group:
Our experimental group consists of the four groups of seeds we planted in the deep water culture cups.
Control Group:
Our control group consists of the four groups of seeds that we planted in a pot of regularly watered clay pellets that will be exposed to the same light source as that of the aquaponics system.
Unexpected challenges:
Thus far, we have encountered two main issues. The first was that our seeds did not germinate in the deep water culture. Our second problem was the long weekend due to MLK Day. Though we fed our fish extra on Friday 1/15, three of them died over the three-day weekend, an event which we attribute to starvation.
Additionally, we may have failed to keep the water at a constant temperature, which could also be a cause of death of a fourth fish.
How have you changed the protocol to address those challenges?
We fixed the germination issue by running strips of paper towel up through the plastic cups and placing the seeds on those. The paper towels wick water up out of the tank and keep the seeds constantly moist, and as of today (1/21) 8 of 16 seeds had germinated. To prevent more fish from starving, we now feed them two to three times a day with an extra feeding on Friday, and our remaining seven fish are growing well.
There are several issues associated with weekends: temperature fluctuations and a lack of day and night cycles. To address these issues, we will insert a heater and add a timer to the lights (to turn the lights on or off every twelve hours), respectively.
How your experiment addresses Energy Dynamics:
Our experiment deals with the usefulness of nitrogenous fish waste as well as optimal levels of nitrites, nitrates, and ammonia for both plant and fish health (especially as it relates to minimizing levels of ammonia). The aquaponics unit requires nitrogen-fixing bacteria that metabolize ammonia to convert them into nitrates, which are, in turn, broken down into nitrites. Nitrosomonas and Nitrobacter have different pH ranges: 7.8-8.0, and 7.3-7.5, respectively; however, cold conditions are inhospitable to them.
The culminating measurements of plant mass as well as the periodic photosynthesis rate measurements relate to the rate of nutrient cycling as well as primary productivity for a potential ecosystem.
Three died over the MLK holiday, most likely due to underfeeding.
We also noticed that one of our fish was partially cannibalized (which supports our above possible explanation).
The fourth one died today, of causes later discussed in this post.
Lots of questions have been asked by some of our readers of the previous aquaponics post. We'll answer them here.
A revised hypothesis:
If a deep water culture aquaponics system is arranged to grow basil (Ocimum basilicum), parsley (Petrosilenium crispum), and other similar leafy plants, then the plants in the aquaponics system will grow faster and larger than plants in a regular soil bed.
From Our Literature Review:
“Again, it [Deep Water Culture] is better suited to growing herbs and leafy green vegetables than plants with bigger root systems and fruiting varieties.”
"Different Types of Aquaponics Systems." Different Types of Aquaponics Systems. Aquaponics and You, n.d. Web. 06 Dec. 2015. <http://www.aquaponicsandyou.com/aquaponics-systems/different-types-of-aquaponics-systems/>.
“We have found that the aquaponic plants grow and produce faster in the system than in a traditional garden.”
"Aquaponics How To." : Aquaponics Plants. Aquaponics HowTo, 2016. Web. 21 Jan. 2016. <http://www.aquaponicshowto.com/aquaponics-plants/overview/22/>.
“Rakocy et al. [9] developed commercial-scale aquaponics systems that have been raised Basil, lettuce, okra and other crops successfully with outstanding quality and yields.”
Roy, M., Salam, M.A., Hossain, M.B., & Shamsuddin, M. (2013). Feasibility Study of Aquaponics in Polyculture Pond. World Applied Sciences Journal, 23. 588-592. doi: 10.5829/idosi.wasj.2013.23.05.74168
Our Independent Variable:
Amount of water given to plants in both types of cultivation
Dependent Variables:
Plant height (cm)
Plant mass (grams)
Plant photosynthetic rate (mL water used/s)
Controls:
Hours of light received by plants
Temperature plants are kept at
Nutrients in the soil
Experimental Group:
Our experimental group consists of the four groups of seeds we planted in the deep water culture cups.
Control Group:
Our control group consists of the four groups of seeds that we planted in a pot of regularly watered clay pellets that will be exposed to the same light source as that of the aquaponics system.
Unexpected challenges:
Thus far, we have encountered two main issues. The first was that our seeds did not germinate in the deep water culture. Our second problem was the long weekend due to MLK Day. Though we fed our fish extra on Friday 1/15, three of them died over the three-day weekend, an event which we attribute to starvation.
Additionally, we may have failed to keep the water at a constant temperature, which could also be a cause of death of a fourth fish.
How have you changed the protocol to address those challenges?
We fixed the germination issue by running strips of paper towel up through the plastic cups and placing the seeds on those. The paper towels wick water up out of the tank and keep the seeds constantly moist, and as of today (1/21) 8 of 16 seeds had germinated. To prevent more fish from starving, we now feed them two to three times a day with an extra feeding on Friday, and our remaining seven fish are growing well.
There are several issues associated with weekends: temperature fluctuations and a lack of day and night cycles. To address these issues, we will insert a heater and add a timer to the lights (to turn the lights on or off every twelve hours), respectively.
How your experiment addresses Energy Dynamics:
Our experiment deals with the usefulness of nitrogenous fish waste as well as optimal levels of nitrites, nitrates, and ammonia for both plant and fish health (especially as it relates to minimizing levels of ammonia). The aquaponics unit requires nitrogen-fixing bacteria that metabolize ammonia to convert them into nitrates, which are, in turn, broken down into nitrites. Nitrosomonas and Nitrobacter have different pH ranges: 7.8-8.0, and 7.3-7.5, respectively; however, cold conditions are inhospitable to them.
The culminating measurements of plant mass as well as the periodic photosynthesis rate measurements relate to the rate of nutrient cycling as well as primary productivity for a potential ecosystem.