Why I wont get fish for now and compost tea experiment

The farm from above

Its been over a month and half now that I have set up the tower farm. In the process of cycling, I have discovered that eggshell can release ammonia (I should have guessed right ?), that pH drops quickly once the beneficial bacteria are established, and that the pH climbs back up in absence of new ammonia. I have also lost my green onion and basil.

The farm from bellow

pH has decreased then increased since no new ammonia was added

Since the system has "cycled", I have hesitated in what fish to get. I will not get fish for now. Why that ? After all the point aquaponics it to get fish to right ?
The reason is that I decided to have an apprenticeship about aquaponics with  Citizen Schools and while discussing with the Citizen Schools people, the fish seemed to be a down side for my plan, so I ruthlessly removed the fish from the picture.

Citizen schools is an association that brings professionals to teach after hours classes (apprenticeships and other programs) to selected middle schools in NYC. Only schools that have 85% of student who are eligible for free or reduced lunch due to their parents low income. Since the fall semester I have been volunteering there for an apprenticeship where we teach our students about heart health. Anyway, A few weeks back I proposed to have an apprenticeship where we would build an aquaponic system with the students and learn about the basic science behind it. So after discussion with the school staff I settled for an "other"ponic system, instead.


Since my all point about starting the system was not only to grow some food at home, but also on a sustainable manner, hydroponic seems like a bad alternative to aquaponics. From the sustainability point of view, hydroponic seems a bit difficult given the need to do full water change, and the need for concentrated fertilizers. An Internet search for compost tea tends to make one inclined to believe that compost tea is the panacea for organic gardening, because of beneficial microbes and a balanced NPK. This is why I have been experimenting with compost tea.

The farm has cycled, and nitrate dropped to 0

I have been making compost tea in the last 3 week ends, increasing the amount of worm compost each week. After "brewing" the tea, I measure the amounts of nitrate and ammonia. So far, I was not able to have a nitrate (or ammonia) level above the detection limit. last week end, I have "brewed" a compost tea using 1/4 of a cup of worm compost, 1 table spoon of molasseses (unsulfured) and shredded seaweeds in 2 cups of water, brewed it for a day and half. After a days and half, it still smelled like molasseses (I like that smell).  I also added some of this greengrow plant food, very diluted. Because I have just seen the nitrates dropping, I decided to add some ammonia source, I though about eggshells, but the pH has increased to 7.4; so given the pka of 9 for calcium carbonate (witch is what eggshells are made of)  I am not sure it is a good idea. Instead I bough a 1/2 gallon bottle of ammonia at the dollars store and added one mL (a bit less than 1/4 of a teaspoon) of it on Monday and Tuesday ( gave ~ 1 ppm reading) nothing yesterday, and now ammonia is back to 0. I will keep adding 1ml everyday for now, until I figure out how to make a strong enough compost tea (if that is possible).
I am keeping track of my experiment hoping that I could make a sustainable "tea"ponic system for the school.

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The worm experiment update 2

The 3 bins on top of the flow through crate

A few weeks back, I have started the experiment suggested by Bentley compost guy. The basic idea, is to take 2 juvenile worms, and let then grow and reproduce in a small container.
Since I have started the experiment, I set up 3 bins, 1 with 2 juveniles, 1 with one juvenile (some worms may be able to auto reproduce) and 1 with a mature worm (mature worm may be fertilized, so we should be able to see population growth there).  The mini bins have been checked every 10 days, and until yesterdays check, I have not seen any cocoons.

Cocoon, right in the center

This time I have found 4 cocoons, and 3 worms in the 2 juvenile bin! That mean that I have missed at least one cocoon in the last 2 checks, as a cocoon should take around 20 days to hatch depending on temperature and other condition. On the right is the picture of one of the cocoon I found, next time Ill use an actual camera to get a better picture. The yellow dot in the middle is the cocoon, the colour of a cocoon is an indication of its development stage: yellow is newly layer, brown is close to hatch. All 4 cocoon I fond were yellow, expect this one that was brown on one side, but yellow on the other side (I have taken the picture showing mostly the yellow side otherwise the phone camera does not show it.)

For the 1 worm bins, I have not seen any cocoons, But I will see if worms "appear" as it is pretty difficult to see the cocoons. I have noticed that when I make compost tea, the cocoons have tendency to float on the top, maybe I should drawn the mini-bins to get a more accurate cocoon counts. 

Overall the worms were rather sitting in the bottom of the bins, where it is quite soggy, it is a bit different form the worm crate, where they are dispersed throughout all of it, but I suspect that the population density has something to do with it, in the worm crate the "sweet" spot would rather be overcrowded, forcing the worms to use all of the available space.

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Update of the vertical teaponic system and the compost tea experiment

The parsley and the small collard greens

  Things seem to be going well in the vertical farm, expept the parlsey, I made the mistake of plugging the extra light for the all day on friday, and when i came back in the evening, a couple of the leaves looked dried up ... Also, It overall seem to not be as green anymore- I though maybe not enough light- but it could be also anot enough nitrate. But today there is a new leaf growing on it, so it probably will be good. 

The green onions are growing nicely and this growth has attracted the lovely kitty who palyed with it. have transferred poted plants on the window seal so the cat does not have acess to it anymore. 

Given the nice growth of the collard greens (and green onions) I decided to count the number of leaves and the size of the biggest leaf just for the heck of it. The longest green onion leaf is just below 11 inches (30 cm) long, the longest collard greens is 2 inches (6 cm), and the parsley is 7 inches (17.7cm). Each of the 4 green onion has 3 leaves, the parsley has 9 leaves, and the biggest collard green has 9 leaves. I took a few pictures of the plants to get an idea of the progression. 

The small collard greens - pulled out to show the small roots growing out of the stem.

 The bigger collard greens, with plenty of leaves growing from it.

A view of the whole teaponic system. 

On the tea" side of the things, this week using 1.5 cups of worm compost for 2 cups of water, it seems that I got some traces of nitrates. Given the color of the tea, I really have to give a try at the stips style tests. But see the picture below, it when from a dark brown to a  "redder" dark brown after the incubation. I think it could be the apparition of some of the red of the API kit that changed the color this way, indicating that therre is some sufficient nitrate to change the color. I will get a set of test strips for next weeks tea and update.

The systems ammonia keeps showing traces (what i add) but it does not accumulate - showing that is really is cycle. Also Nitrate do not seem to accumulate either, they have been indetectable since thier "diseaperance "from the water a few weeks back, after the system had fully cycled.

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Update on the vertical garden and compost tea experiment

It now has been almost 2 months that I built the vertical farm ! and things are going along pretty well ! I have some parsley growing, a few green onions, 2 collard green plants and swiss chard. The parsley that got burned by the light bulb that was too close almost made it, but I pulled it out to make space for the seedlings to come. A few weeks back Ive planted the core of 2 collard greens and one of a swiss chard, just to see, and last weekend when doing a bit of cleaning I pulled a bit on one of the collard greens and was happy to see a few tiny roots that where growing out of it ! The collards, swiss chard and onions are all "salvage" from the kitchen scraps.

I just seeded a few seeds last week end : Cilantro, Parsley, Roquette, Letuce (black seed simpson), Swiss chard, Summerlong basil, and Spinach. I hope to be able to plant all of that - to see how many plants I can put in there.

I have kept adding 2 mL of NH4OH to make sure that there is enough nitrogen. I have kept increasing the amount of compost I use to make the compost tea, so far I am at 1 cup - which is 240 mL - of worm compost for 2 cups (480 mL) of water. Depending on the volume in the tank I am either using "new" water, or water form the system, and "brew" it for about a day and a half. After that i measure if there is ammonia and nitrate in there. Given the coloration from the compost (of course filtered) its really difficult to tell, but so far, it does not seem that there is large amount of it. Possibly, the different compounds of the compost interfere with the kits reactions. I may get these strips to see if the results are different form the API kit I have. The systems water has some ammonia (the one i add) but no nitrite or nitrate accumulating. The Ph seem stable around 7 ish : the ammonium hydroxyl I add probably buffers the acidification due to nitrification, as well as the compost tea.
Also exiting things are happening at the school I volunteer, but there will be more about it in a little.

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