It’s the week before harvest, and it seems that everything is going just fine. We still have great plant growth, everything working well, and I noticed that although I’ve been checking the pH in every single tube and the reservoir weekly, it’s been perfect–what a nice surprise that I didn’t have to deal with adjusting it. We topped off the reservoir for the thanksgiving break, but it really didn’t need it. The systems been going for more than a month and hasn’t even used up two gallons of water. Definitely seeing what they mean by saying NFT systems are water efficient.
Our plants are continuing to grow just fine. The first plant is growing tremendously, and the other two are growing just fine, although not as fast as we’d like. We noticed buildup of waste in the tubes. This is because of our drainage system which is raised. Now that we see this, we realize that we probably should have drilled properly sized holes instead of raising the outlet pipe, since the waste has no way of draining into the reservoir where it can be collected on the filter attached to the pump.
We’ve noticed a small leak in our system where the pump hose goes into pvc tubes. Its only a slight drip though, and it drips right back into the reservoir, so we decided to ignore it for now, since we’d have to shut down and drain the system to fix it, and our plants are still growing just fine.
Over the weekend both of the seeds we planted in the two growing tubes began to grow! They’re both extremely young, but hopefully they’ll grow fairly fast. the different type of seed that we chose for the two replants grows a bit quicker than the first seed, so hopefully that will kind of even everything out
Also, the first seed is growing just fine.
We’re surprised as to how little water is evaporating or being taken by the plants. We’ve only had to fill the system once since we first started, and that was just really a top off.
Two weeks after our first plantings, we still have had only one baby mesclun seed begin to grow, so we decided to replant the other two plants. we chose to plant mesclun instead of baby mesculn since it has a shorter germination period and a shorter harvest period, and will therefore hopefully be ready for harvest around the same period that the one baby mesculn will be ready for harvest.
In other news, our system has yet to leak again, so we think we have that problem solved.
Also, Brett made a larger reservoir for the bottom section of our garden out of polycarbonate, made to fit exactly into the box, which increased our reservoir volume by about 1/3rd, so this should enable us to run the garden for longer periods of time without topping off the system, allowing for the system to be more self-sufficient.
After running the system since Tuesday morning, we came into the lab to notice the wood around the bottom of the box buckled outwards due to water swelling. After opening the garden, we were not able to discover where the leak came from, but we think it may be due to us adding to much of the nutrient solution in the beginning. After cleaning the water up and inspecting the whole system for any sign of a leak, we decided to fill the system back up, but this time with less water, and run the system for an hour or two to see if it continues to leak.
on a plus side though, one of the plants began to sprout, so at least we know we’re going in the right direction if this leak is sorted out!
(update from two hours later)
After checking the system two hours later, we haven’t found any leaks, so it looks as if we’re up and running again.
We still dont know what caused our leak, although we feel that it may have been we just overfilled the system the first time.
After Brett finished the construction and testing of the hydroponic system over the weekend, we were finally able to place it under the grow light in the lab and fill it with the nutrient solution. After running it for a few minutes to make sure everything was alright, we planted three different baby mesclun seeds in our presoaked rock wool, and we’re now simply waiting for them to start growing.
Our hydroponics system is a simple 9″x10″x12″ wooden box that with a separate top and bottom tray. the bottom tray holds our water pump and reservoir, and the top holds three PVC tubes which each hold one plant in rock wool. the pump is run into a PVC delivery system which, through the ball valves on each tube, allow us to fine-tune the amount of water each plant receives. within each tube the water flows from the inlet pipe, through the tube, passing through the rock-wool, and out the outlet tube which is raised to ensure a constant water depth to keep the rock-wool constantly submerged. this system is known as a continuous solution culture, since the plant is constantly receiving new nutrients. Lastly, the water falls out from the tube into the reservoir, aerating itself when it falls.
Pictures will come soon