Tuesday, 26 January 2016

Duke says Hi

Duke says hi

Second Foray Into Hydroponics

My last post documented my very first attempt at growing plants using aquaponics. It failed for several reasons:

  1. Turtle kept dislodging the plants
  2. I kept dislodging the plants when cleaning the tank
  3. Not sure the nutrients were present in high enough concentrations 
The plants grew to about 3cm and then stayed there until I ended the experiment.

This time around I kept it a little simpler and opted for straight hydroponic setup. A nutrient solution in the base of the container is wicked up to the grow media via a strip of fabric. The roots should eventually make it all the way down to the solution, taking in both air an water. The light is a CFL bulb which is pretty weak but cheap to run. A nearby window supplements it during the day.

I'm growing lettuce and basil.

Three weeks later and growth is a little disappointing:

I'm not sure but I think light and heat might be the limiting factors. 

Meanwhile I've started propagating some Java Fern, an aquatic plant, from the aquarium in a nutrient solution in an attempt to increase the amount of greenery in the aquarium.

Tuesday, 25 August 2015

First Forays into Aquaponics

Now that the turtle tank (minus the turtle) is up and running I've turned my attention to growing lettuces hydroponically using the aquarium water as the nutrient solution. The tanks has not quite completed cycling yet. The ammonia levels are almost back to zero and the nitrite levels have peaked but the nitrate levels are only just beginning to climb. This seems like a good time to begin germinating some seedlings so that in a week or so they will be ready to take up the nutrients from the water.

I constructed a raft, to hold three net pots just below the water level. The raft is actually suspended from the cross-brace of the aquarium lid. I will have to make this a little more turtle safe later on, but I want to see if it works first. Three days ago I planted red lettuce seeds about 1/4" deep into some 1" cubes of rockwool. The first shoots are just breaking the surface. You can only just make them out in the middle pot shown below.

It seems to me that the biggest risk is that the nutrient level in the aquarium water may not be sufficient to achieve true aquaponics growth rates but If I can grow even a modest amount of lettuce to feed to the turtle then that would make this project worthwhile.