Ok... enough with equipment. Time to show off some produce.

Keep in mind this is the end of October, not exactly the most productive time of year for gardeners. But nonetheless my little IBC tote system(s) are still quite productive. I keep waiting for everything to generally finish "doing their thing" so I can clean the bed out and restart with leafy greens, but everything just keeps going, and going, and going.....

Here's a wide shot of the first IBC tote system.

I am totally amazed that even now this late in the season how productive this little patch of plants are. The tall ones are Okra. I am getting around 5 or 6 nice sized okra *per day* from these plants. This comes out to about this much a week:

Here's a close up of one before I picked it this morning:

I also harvested some of my climbing New Zealand spinach and made a wonderful omelette with it. Here's a close up of what it looks like in the plant bed:

Also tucked in between the monster okra are some jalapino plants. What is interesting about these peppers is that the fruits were harvested in the late spring (made some great salsa with them!). I didn't bother to pull out the plants because the plan was to completely clean out the bed as soon as the okra stopped producing. Little did I know that I apparently have an immortal strain of okra. Anyway, these pepper plants are now producing their second batch of fruit!

While harvesting part of my breakfast this morning I had an awesome surprise! I have this huge eggplant that has continued to flower for the past several months but has never produced fruit. I was snipping the spinach and saw a large fruit out of the corner of my eye. I thought to myself "that's a *huge* jalapino, but when I looked closer, lo and behold, it's a softball sized eggplant that has been hiding in the middle of the thicket.

On the opposite side of the bed from the spinach is a monster basil plant. I've made a couple of nice batches of pesto from it and it is still quite happily producing. I plan to pick some more as soon as I finish writing this to make some pesto and cream cheese dip for a Halloween party this evening.

Ok, enough with the original bed, on to the new one. As I mentioned in an earlier entry, I found that my fish tank can support quite a bit more growth than the tiny (but uber productive) original bed. So... I built a 4'x8' "lumber and liner" bed beside it, filled it with gravel, put in a nice bell siphon, ran a hose over to it, and planted some more stuff. Here's a picture of the addition:

And here are a few shots of the new "babies".

 Kohlrabi:

Chard:

Cabbage and Collards:

And here's the little poopers that make it all possible!

More on bell siphons...

I recently added a new 4'x8' media based bed to my setup and am running it off of the original tank I created from the IBC tote. Because it has a larger area for the water to trickle through I want to have a good ebb and flow cycle in order to keep dead spots from happening. With an ebb and flow system, not only do you suck air down into the media each time the water goes down, you also ensure that the entire bed gets a nice dose of fresh water with each cycle as well.

One of the inherent problems with bell siphons in larger beds is that due to the bigger surface area the water level tends to drop relatively slowly as the water siphons out. This means that when you hit the bottom of the cycle it is difficult to get the siphon to break so the bed can fill again. I did a bit of net surfin' and found a guy out there with an absolutely brilliant solution to this problem.

Basically he solved the problem by adding a small auxiliary tube to the bell siphon. NOTE: the top of this tube needs to be *below* the height of the internal stand pipe. The bottom end of this tube is cut just above the "teeth" of the bell at the point where you want the siphon to stop (your lowest water level). The tube is placed inside a small cup (A 2" PVC end cap works well). When the water level falls to the bottom of the tube it will also be below the edges of the cup. The water inside the cup quickly gets slurped up in the siphon, but the cup keeps additional water from pouring in. This leaves a nice protected air pocket that will easily break the siphon so the cycle can start over again.

Here's a link to a YouTube video that has some excellent illustrations showing how this works.

What to do about cold weather....

Although our weather is very mild around Austin, Texas, we do cool off in the winter. The severity can range from only a few light freezes throughout the winter to a few weeks of ice and below freezing temperatures. In either case, you can still grow some great veggies in an aquaponics system like the one describe if you take a few easy steps to protect the fish and plants.

Talapia don't like cold temperatures. So, unless you want to wake up one morning to a tank of fish-cicles you need to find a way to heat your water. The easiest I have found is to go to your local fish store and purchase a heater designed for tropical fish tanks. The largest size I have seen in the local pet mega-mart is a 300 watt unit designed for large fish tanks. While these probably won't do the trick if you live in Minnesota, around here they are enough to knock the cold off as long as you don't have multiple days of sub-freezing weather with no sun during the day.

For the plants, it's pretty darned easy to build a "hoop house" over the grow bed. Basically, this is just some PVC pipe bent into an arc and covered with clear plastic.

Here is a picture of the one I built last year:

Let's talk bugs...

In looking over the spreadsheet I posted I now remember that I had quite a time with caterpillars last fall. Last year was kind of unusual for us weather wise around here. It was very dry throughout the summer, which in itself is not all that unusual. However, when we did start getting some rain it was pretty late in the year. Additionally, we had a prolonged "indian summer", which is the inevitable late season warm spell that generally punctuates the transition between summer and fall around here. With the combination of the two the critters seemed to think that spring was early and my nice leafy greens were one of the few games in town.

So, how the neck do you keep the caterpillars from ravaging your crops without dumping a bunch of toxic crap into your system?

One of the most effective controls I have found is Neem oil. Neem is a plant that is known for its antibacterial properties and is widely used in some parts of the world as an herbal remedy. The bugs, however, find the oil of this particular plant to be distasteful. I purchased a small bottle of Neem oil at my local organic gardening store. Every few days I would put about a cap full in a small spray bottle with a bit of liquid soap as an emulsifier and gave it a good shake. I would then spray the leaves of the plants.

It doesn't kill the caterpillars, it just makes the plants distasteful to them so they go elsewhere for food. It  was pretty darned effective as well as environmentally friendly.

So... about water quality...

Once you get your system set up, you have your media installed, and you have hooked up a pump to recirculate the water you need to let it run for a week or so to let the good bacteria build up and generally let the system settle.

You want to keep your pH around 7. You also want to make sure that your ammonia levels don't rise too high as ammonia is toxic to the fish. It's a good idea to invest in a good test kit to check your water chemestry. You can usually find a suitable kit at your local fish store.

For the first few months I was pretty religious about checking the chemistry every day to understand how the system was working. Turns out, once it was up and running well the readings were pretty darned stable.

Here's a link to a google docs spreadsheet with all of my chemistry readings for the first couple of months in my first system.

Heres a picture of the system just after I got my first plants in.

The first round of plants were mostly vegetative. Things like lettuce, kale, and cabbage. You can see what I harvested while I was keeping records by looking at the "Harvest" tab in the above spreadsheet.

Here's what the garden looked like in July:

Don't know if you can see all the different plants in your browser, but the tall ones are okra. There is a really nice eggplant on one side and a spaghetti squash trailing down the other. In the back there is some climbing spinach as well as a couple of patio tomatoes and a really nice basil plant.

Ebb and flow systems

There are several methods to create an ebb and flow cycle in your system. One of the simplest is to purchase a programmable timer to hook up to your pump. Assuming you plumb the system such that the water flows into the grow bed from the bottom, the timer will cause the grow bed to fill when the pump is active and the water will trickle back through the pump and into your fish tank when the pump is not active. The down side is that timers can be expensive and adds a bit of technology into the mix. The up side is they are pretty darned reliable and easy to use.

One thing to note with timers is that you will need to put some sort of overflow/outflow mechanism to prevent over filling. The water needs to have a path to drain back into your fish tank at the maximum height of your grow bed so that even if the pump keeps running you will  not overflow the sides of the bed.

Bell siphons are another low tech way to implement an ebb and flow cycle. Basically all a bell siphon consists of is a small pipe that sticks up from your main outlet and is cut off just below the maximum height you want your water level. A larger pipe with holes in the bottom to allow water in is placed over the smaller pipe. When the water level reaches the top of the outflow pipe it will begin to spill over and create a suction. This suction will be maintained until the water level falls below the holes in the outer pipe and the suction is broken. The cycle then starts over again.

A couple of items of note:

Bell siphons generally work best if you "neck down" the bottom outflow pipe to a much smaller diameter pipe. The reason for this is that you need to keep the outflow pipe completely at capacity otherwise the suction will break more easily. So... if the top of the outflow is larger around than the bottom there won't be a problem keeping the smaller pipe at the bottom supplied with sufficient flow to keep it full.

Also, you need to make sure that your inflow is *less* than the capacity of your outflow pipe. If you are putting more water in than can drain out the bell siphon your grow bed will never empty so it can't complete the cycle.

In short... the bell siphon is a bit of a balancing act, but IMHO well worth the effort.

Here are some illustrations:

Ok... so some of y'all might have noticed that in the above video the pipes on the bottom of my outflow are the same diameter as the top part that controls the maximum water level. While this works, I found from trial and error after filming this that reducing the bottom part of the outflow to a considerably smaller size was much more trouble free.

So... there you have it...

Enjoy!