Every quarter or so, I share the nutrient analysis of the aquaponics system water. I try to test the system water every two weeks or so. This is the 4th report. Using a photometer, I can get a handle on what is going on in our water and that’s been amazingly helpful. It’s true, you really do have to measure in order to manage. As I mentioned in my last report, sharing this information helps us all to see how one system is performing. It is my hope that this will inspire others to share system info so that we can compare notes and contribute to a healthy aquaponics industry.
So what’s been going on since March? Well, let’s dive into the numbers and see. Read More
I went to the Eating Insects Conference in Detroit and had the privilege of joining the fantastic folks at Detroit Ento for an amazing meal full of delicious insects.
Upon walking in the door, we were greeted with a meal worm infused cocktail that had me and my dinner mates buzzing about its silky sweetness as we gathered for the big meal. Apparently, when you grind up meal worms and then strain out the chitin-y bits, it adds a silky smooth texture to the simple syrup to which it is added. Yum. Had me wondering…if it’s so good in a cocktail, the home brewer in me is thinking a larval lager might be worth a try.
After the drink gave us some wings, a good look at the menu had us chirping like crickets. We could all sense the dinner was about to jumpstart our hedonistic plunge into entomophagy. Everyone was anticipating the delicious 5 course dinner we were about to share with 30 strangers that you just knew would instantly become friends after this. It felt like good ol’ family fun sitting around the table sharing stories and not one person was grossed out as far as I could tell. I guess if you come to a dinner showcasing insects as food, you kind of have the gross thing already dealt with in your mind. Read More
Recently, I had the privilege of making a trip out to one of the coolest conferences I’ve ever attended, Eating Insects: Exploring the culture of insects as food and feed. Entomophagy, the technical term for eating insects, is an emerging industry in the United States. Even in a wealthy country like the US, hunger is still a huge problem. Economical and environmentally friendly alternative proteins are being looked at with great hope. To meet the needs of an expanding population, we need to consider all of the protein options we have available. This includes eating insects.
Before you squirm in your seat, eating insects has been around for a very long time in other cultures. And while it may not be for everyone, insect protein can be a viable option for feeding fish, poultry, and other omnivorous livestock with a much lower carbon footprint than traditional proteins like soy and fishmeal.
What set this conference apart from others was the overwhelming sense of self awareness this burgeoning industry has. It was very clear to me by lunch time on the first day that everyone in the room, while entomophagy enthusiasts, understood that we are not going to convince everyone we know to try, and dare I say, enjoy, insects as food. Heck, even I was a little concerned about the idea and I flew 2000 miles to be there! My trepidation was alleviated in short work when I attended the dinner hosted by Detroit Ento later in the evening as detailed in another blog post.
One non profit organization called Little Herds was there to present some of the incredible edible insect work they’ve been doing with kids. I like their educational model. You may not be able to convince adults to eat insects, but kids love them. And kids who eat insects will be adults who eat insects!
The conference was well attended, I’m guessing 300 people or so. That’s quite a few folks for a bug eating meeting. The presentations included topics like the perceptions of edible insects, the environmentally friendly benefits of raising insects as compared to other proteins, edible insects in other countries, and successes and failures of raising insects. Each of the three days was filled with intriguing presentations with a fancy dinner Thursday night and a vendor expo on Friday night. The vendor expo was a thrill because we got to try just about every insect product on the market, it seemed.
I happened to miss my shuttle to the expo and the guys from Entomo Farms were kind enough to give me a ride there. Great guys and amazing insect farmers. The pictures they shared from the Entomo Farms facility and their tasty products were top notch. And I’m not saying that because of the free ride! They are the real deal when it comes to large scale insect farming and were very open and informed. I enjoyed our conversations about production and I even got to share some of the work we are doing at TomKat Ranch growing soil with grass fed/ grass finished cattle. It’s something I spoke to a lot of people at the conference about because insect farmers often times compare inefficient conventional beef production to the amazing efficiencies of insect farming. My point is that, yes, insect farming is probably always going to be more efficient from an input perspective, but the benefits of soil restoration, carbon sequestration, and increased soil water holding capacity gained from grassfed/grass finished production should also be considered in the full life cycle analysis when breaking things out.
Amongst the vendors was a very special man from Missouri named Paul Landkamer sharing his favorite bugs on a platter (pictured above) and he was there only for the love of entomophagy. Nothing to sell, but enthusiasm, and it was highly contagious. As he described his entomological offerings, he mentioned his entomophagy club back home. Figuring it probably consisted of just Paul, I asked how many in the show-me-state were in his club? He answered 30 people! Well, after trying the different insects he had to offer, I can definitely understand why he has so many members. Paul had a platter of differently prepared insects that were roasted or sweet pickled. The roasted ones were decent, but the sweet pickled bugs will knock your socks off they are so delightful. He was a real highlight of the trip.
Eating Insects was hosted by Wayne State University and organized by anthropologist Julie Lesnik. This inaugural conference was an immediate success. I look forward to where we go from here and can’t wait until next year! Read More
The original Hopper Hopper I made has worked out pretty well. It is a bin, some duct tape, and a modified 5 gallon water bottle to act as a funnel. The whole idea reminds me of that scene in Return of the Jedi, where they’re outside Jabba the Hut’s lair in the sand above that thing called a sarlacc and people are falling in it’s toothy mouth. Recently, I made one adjustment in using a larger bin and moving the funnel to one side. Having the extra space on one side of the bin now allows me to tap the egg cartons full of crickets on one side of the bin so that frass and molts can easily drop and be vacuumed up after herding the crickets toward the funnel. This change has helped with the time it takes to harvest. Before, I was taking too much time trying to keep the frass out of the funnel. Now, it’s much simpler. There are still some stragglers that I have to hand pick and that’s always fun, but this system works for small producers as far as I can tell. I should add that I’m working on another way to harvest crickets and will be posting about our trials soon so you can see how that develops from the beginning.
The white worm culture is thriving. It’s interesting how big they actually get when you purposefully feed them. As I mentioned in my previous white worms post, we already have enchytraeids in the Vermiculture system. They are much skinnier when you see them in the worm castings. When I first heard of culturing white worms for fish food I was dubious since my experience was they were these thin little hair-like worms. Not so. They plump up quite nice as you can see. I’ve been feeding them chicken scratch paste. I mix a little water with chicken scratch and stir into a paste. The culture medium is worm castings. When I want to feed them, I make a small row in the middle of the bin and put the food paste in there and cover it up to prevent flies.
Honestly, even in their current plump state I’m still wondering how in the world these tiny things translate to serious useable protein. It’s crazy how the Soviets used them as feed for white sturgeon production. I’m inspired by their huge system of bins and look forward to cracking the production code. White worms like a temperature range of 59-77F and seem to prefer a neutral pH. They are euryhaline which means you can use fresh or saltwater for moisture and use them as a live feed in either. They are pretty easy to raise and I look forward to seeing if they translate into something we can really use. A huge thanks to Elizabeth Fairchild, PhD from University of New Hampshire for sending me the culture.
White worms profile:
Here’s a look at the aquaponics system water usage per month for the last 11 months. The monthly data is after the page break. The 4000 gallon system usage averages about 540 gallons per month producing around 250-300 heads of lettuce each month. That’s 18 gallons per day and takes roughly 2 gallons per head of lettuce on average. Pretty efficient system. I’m excited to get our mineralization tank installed to keep even more water in the system. Currently, everytime I flush the filter, the water is lost to the ground outside. Keeping it in a mineralization tank to extract even more nutrients and save water will add to the nutrient density of the produce and the water efficiency of the overall system.
Perusing the internet, the typical average to produce a one pound head of field grown lettuce is between 16 and 23 gallons of water. Our lettuce heads are a little less than a pound averaging close to 400 grams. So if we produce 300 heads at 400g each that is the equivalent of 264 heads of field grown lettuce at 454g each. Aquaponics lettuce at 2 gal per head equals 600 gallons to produce and at 16 gallons per head of field grown lettuce, it takes 4,224 gallons to produce. Pretty big difference.
Can we replace all field grown lettuce with Aquaponics? I don’t know that we could do that. There is a lot more infrastructure required to grow aquaponic lettuce. You need a greenhouse in most cases and heat in the cooler climates. However, in places where water and/or arable land is scarce, aquaponics is a solution worth considering. One grower in Hawaii, Zac Hosler of Living Aquaponics is converting lava fields over to aquaponics. How great is that? Farming land that you couldn’t even drill a seed into and producing. As droughts become more common in particular areas, aquaponics serves a great alternative to conventional farming affording the ability to grow nutritional produce with very little water.
Continuous Flow Through Reactor is a funny name for a worm bin. It sounds complex, but it’s probably the simplest worm bin design you can have. Basically, it’s a box with a grid at the bottom as shown in the Wormery post here on this blog. Professionally engineered Continuous Flow Through Reactors (CFTR) have a winch at the bottom of the system on both sides to pull a knife-like bar across the bottom to extract the worm castings. This removal allows for more space to put your feedstock on top of the system for a continuous flow. Food on top. Castings on the bottom. Most of the worms and other critters stay at the top of the system where the food is. We went basic and used wood with some plastic sheeting as a liner for the sides of the CFTR and 2”x4” welded wire for the bottom.
The welded wire is heavy duty and while it may seem like the openings are too big, we used cardboard when we started to lay over it to keep the contents of the worm bin inside. After a couple of weeks, the cardboard breaks down and the castings are sticky enough that they don’t drop through without some sort of agitation. We don’t have the cutting bar at the bottom so I just use a rake to scratch off the castings. It certainly doesn’t work as well as a winch powered system, but it works just fine on a small scale. The 2×4” openings help a lot here. When my bins fill up faster than I can scratch, it’s a pretty simple fix to take the top layers of the bin where all of the worms are and put them into a holding space. Then, the castings in the lower 2/3s of the system can be scooped out. It’s a little bit more work, but the castings are rich and crumbly and oh so nice.
I really like the Continuous Flow Through design for worm bins because they are extremely easy to build and easy to take care of as they allow for more air exposure eliminating the worm “tea” aspect of enclosed worm bins. The leachate or “tea” that accumulates at the bottom of an enclosed worm bin is not really that good for you or your plants. It is typically high in salts and provides habitat for unfriendly microbes. If it is diluted and aerated in a compost tea brewer, it will be safer to use, but ultimately your worm castings will produce a better, healthier tea if you just use those and toss the leachate. This is why I like the Continuous Flow Through design. The open bottom and top allow for more oxygen availability to the system for what I believe to be healthier worm castings and a happier worm herd. It’s important to size your bin so that it fits your incoming feedstock. That way, your bin isn’t too small or too large to accept the incoming food and can be dealt with accordingly to avoid odors.
So even though my CFTR isn’t quite like the engineered systems, it works extremely well and the price is within anyone’s budget. Being able to build a system to match your needs is crucial to a healthy worm herd that can take care of your feedstock. The cool thing is, once you’ve built one, you can build another fairly easily should your feedstock increase. And on top of all of the benefits, Continuous Flow Through Reactor just sounds cool.
There are a lot of different types of worm bins that people use for vermiculture. You can build one or buy one, but they all have similar management techniques that you can employ to reduce odors and annoying flies. This is of particular concern when using food scraps as part of your feed stock or all of your feedstock. As anyone who has been on a picnic can attest, flies like food and they are incredibly irritating. They land on your food and eat by spitting their digestive juices out only to quickly mop up the the yummy nutrient sauce they created with their spongey mouth parts. They also like some types of food because it provides a wet place to lay eggs and a nutrient source for the young to get a good start. For our wormery, I’m fairly lucky to have pre composted horse manure to use as a feedstock. Whenever I have food scraps from the lunch room or a large event, I cover the thin layer of food scraps that I’ve spread out on the top of the worm bin with horse manure to prevent the flies from easily accessing the food. This keeps fly populations low and controls odors. If you do not have the horse manure, you can use worm castings from the bin to cover and bury the food scraps. Ideally, you want the food scraps layer to be shallow so that it doesn’t putrefy and create a lot of anaerobic activity because that is where the stinky smells come from. Flies are attracted to putrid smells and know there is good egg laying ahead whenever they find them. If you do not have horse manure or enough castings, consider some peat moss or coconut coir, or shredded card board/paper to get some coverage. When adding any of these materials to the bin, please try and balance out the extra carbon added to the system so your C:N ratios don’t get too out of whack. You essentially want enough to cover the food scraps and have a little dryness on top so as to discourage the flies from finding a nice place to raise a family.