Episode-1355- Aquaponics with Tom Smith — 32 Comments

  1. Why can’t a person integrate several different aquaponic units into an ecosystem; say limited amount of duck/goose waste goes into a pond meant to grow algae, mud bugs and fast growing aquatic plants. Daphnia or tilapia could use the algae. Black soldier fly larvae could turn other wastes into a premium food for several things. Etc, etc, etc. Does it have to be closed loop to qualify as aquaponic?

    • The answer is of course they can. The next answer is to the question of who can, that answer is it depends.

      • Good one. I’m workin on it. Just wondered if I was thinking the right direction.

    • You absolutely can, and I think it’s a great idea. The ideal setup would be a polyculture with as much as possible happening passively, just like in a polyculture pasture situation the insects grow in the ruminant dung passively, and the chickens harvest the insects passively. I doubt the system would be as effective if you had to gather all of the manure, actively manage the growth of the insects and then collect and deliver them to the chickens. When designing an aquatic polyculture, the same principle applies – the more that is done passively the better.

      With regards to the “duck/goose waste” I have two comments: one is that I’ve seen several examples of “duckaponics” work successfully (give the ducks a tank to swim in and circulate that water through a grow bed) BUT all of the systems have pumps that can pass larger solids without clogging or wearing out. You could also filter the water before it goes through the pump, but I think you would end up spending a lot of time cleaning the filter.

      Second comment: If you want to use ducks/geese to fertilize a pond (help algae grow, which is eaten by zooplankton which are eaten by insects and small fish, all 4 of which are eaten by various species of larger fish) – that is a great idea and a common aquaculture practice. By raising livestock (including pigs, chickens etc.) next to (or in the case of waterfowl, on top of) a pond, it makes fertilizing the pond with manure very easy, and this increases the amount of fish that can be raised in the pond. I would call this aquaculture, not aquaponics, because there is no terrestrial plant being grown, but that is really a technicality, haha!

      Sorry for writing an essay, I hope it isn’t so long that you don’t read it!

      • Thank you sir, this is great stuff. Any experience with pacu or shark catfish in aquaculture? I know tropical but fast growing omnivores that get too big for aquariums in a hurry. Put a pacu in stock pond at 8″ in late spring and it winter killed around 5 lbs!

        • Both are great eating and hardy, particularly the shark catfish. TONS of shark catfish is grown in south east asia (much of it is imported to the USA and given the name Swai). I think it is another great fish to culture, but you are exactly right that they are tropical and so their achilles heel is going to be low temperatures. However, if you are in a tropical climate, want to grow them seasonally, or are inside, they should work well!

  2. …and those big ass apple snails in Florida and Hawaii are bound to be a good way to convert vegetation into protein. There’s a hawk or kite of some kind that lives solely on the snails. Gators like em. (Heliciculture)

    Great show, highly interesting. Thanks.

    • Those are what I put in my tanks, never saw em again, 20 in each.

      • Maybe it depends on species or something. I’ve done ok with slugs on a raft in my ibc tank. Trying to put together a pretty big integrated aquaponic greenhouse with a system similar to those used by Growing Power. The turbo snails and limpets in my saltwater tank reproduce like freaks but the sea urchin keeps em thinned down.
        Wonder if anybody has put shroom logs with aquaponics?

    • I think some very interesting experiments could be done with snails. Since you have a saltwater tank, you probably already know this, but I will write it just in case: be careful purchasing and be aware that common names can refer to several different species – some of which may be good for your climate and others which may not be.

  3. Thank you Mr.Smith for sharing this info on what is a relatively new way of having this stuff setup. I have read a little into it on what i could find but i think i learned more on the understanding of this from the podcast than i had from the other websites and video’s i had seen.

    Thanks Jack for choosing the topic and as always leading a great discussion.

    • I’m glad you enjoyed the interview. Good luck researching the topic; if you want to try building a system for a small amount of money, don’t be afraid to build one as small as a 10 gallon aquarium and a growbed. A couple of small goldfish and a few lettuce or herb plants can give you some “hands on learning” in the topic!

  4. Came to Florida in 1967 as project engineer for Boston-based Slade Gorton Seafood Co to design, build and make operational automated equipment to shuck and eviscerate calico scallops. Convincing corporate to miniaturize bulky shore-based equipment, process at sea and return with only with payload, fell on deaf ears. Eventually, no Florida scallop industry.

    Tried organizing a shore-based Mari-culture project for oyster and clam in the early 80’s. Bought land adjacent to the Intra-coastal, built a shellfish hatchery, intended using twice daily sizable tidal rise and fall. All attempts failed due to DNR Permits galore designed prevent an and all such endeavors.

    Florida no longer has a viable shrimp, finfish, shellfish, or any sizble seafood related industry,,, nor will it have as long as existing Tallahassee idiocy prevails…

    Florida Dept of Natural Resources is more powerful than God. Save your money. Do your business elsewhere.

    • Unfortunately for the citizens of this country, Fish and Wildlife, the EPA and many other government agencies have had their boot on the throat of the aquaculture/mariculture industry since the beginning. We could have a tremendously productive aquaculture sector, both marine and freshwater, but the government has so far prevented that.

  5. What do you think of the CHOP (Constant height, one pump) aquaponic system? I made a very small one in my basement, which promptly failed. I was wondering if i would be better off attempting one of the other types, and if i was mistaken to attempt that one first, or if i didn’t do enough research before my attempt, which could very well be the case! Thanks for the show, and keep up the good work!

    Eric M. in Rhode Island

    • Personally, I think “CHOP” is a bit of a misleading term, because I have heard it used to refer to two different types of systems. Some people use it to refers to deep water systems, others use it to refers to flood and drain systems. Plus, in my opinion almost all good systems will only have one pump. Having two pumps is usually a recipe for failure because you will be trying to match the flow rates – which is typically impossible even with two copies of the same pump.
      Is what you are referring to something like this?

      If not, can you give me more information about your system? Also, how did it fail?

    • I hope I don’t come across as critical in my last message, I don’t blame you for using the term “CHOP”, I just want to make sure I understand what kind of system you built.

      • it was gravity fed but not siphon, so it may have been just my own misunderstanding of the system…. i will do more research to find out where i went wrong. the system was similar though. thank you for the help!

        • Did the plant bed fill alternately with water then air? Or alternatively did the plant beds have aerators in them? If neither, then it might have been that your plant roots did not get enough oxygen. Good luck with your further research and building! It sounds like you might be able to modify your system slightly and get it working.

  6. Is Trout doable?

    Would it take a relatively complicated set up?

    Would it be worthwhile or would be sorta like crawfish..maybe not work the effort or exepense.

    I keep hearing conflicting info.

    As a aside…Man could we solve alot if problems with invasive fish species if we took a liking to eating them.

    I agree we are prejudiced against carp. Snakeheads as well.

    • I think you nailed it on the head comparing trout to crawfish if you are talking about typical aquaponics (see second paragraph for an alternative). I love trout, but it is a very sensitive species and it needs a high protein food (expensive). If you did want to grow trout, you would need an excellent and expensive solids filter (not just a settling tank), you would need to keep the temperature cold year-round and you would have to keep a very close eye on your water quality (pH and Ammonia). Can it be done? Yes, but it would be expensive and not particularly efficient.

      Here is something that could be done: trout are typically grown in raceways (flowing water that does not recirculate). At the end of a series of raceways, before discharging the water to the environment, that water could be passed through a grow bed: the plants take the nutrients out, and the water is then discharged to the environment. This helps issues of eutrophication and provides an extra yield.

    • I would also agree about the prejudices against invasive fish species. We could solve the problem by hunting them out of existence!

      Also, a tip for anyone eating carp (or any fish) that they are worried about tasting “earthy”: fillet and skin the fish, then soak the fillets in an acidic liquid (buttermilk is my choice, some people use lemon water) for about an hour prior to cooking. Then, rinse the fillets off and cook them. This usually takes most if not all of the “earthy” flavor out. If you’re really worried about the earthy flavor, soak, rinse and then batter and fry the fish. Nothing tastes bad fried!

      As an aside, the earthy flavor typically comes from the fish eating certain types of blue-green algae, or organisms that consumed those same blue green algae before being eaten by the fish.

  7. I think Tom said what species for outdoors in warm climates but what about cold climates? In a greenhouse?

    Also, does he have some specific suggestions for pumps or heaters for a small (300 gal) system. I can’t seem to decide.

    • The trouble with raising fish in cold climates is that they are cold-blooded. This means they will eat less and grow slower when the temperature is low, but remember that in aquaponics the fish are more of a bonus, so this really isn’t an issue from the production standpoint. Because the fish will eat less, you have to stock more of them for a given grow bed size (grow bed area is determined by how much feed the fish eat daily).
      Now, as to what species to grow, I would recommend catfish, goldfish, or carp/koi. I would also recommend bluegill or largemouth bass (separately, not together), but with two caveats: 1) bluegill grow very slowly and are less efficient at converting feed into body mass 2) largemouth bass need a VERY expensive, high protein food. All of these fish can handle colder temperatures, but are hardy enough to grow well in the aquaponic environment (trout are good for cold climates, but are not particularly hardy).

      For a greenhouse, I would recommend the same species because they will be able to handle to colder temperatures that may occur at night but still eat and grow well during the warmer temperatures during the day. If your temperature stays above 60 F, you can keep tilapia in a greenhouse, but if there is a chance of temperatures dropping lower, I would recommend sticking with the species that can survive cold temperatures.

      As far as pumps and heaters for a 300 gal. system, I would get a pump designed for an outdoor fountain or fish pond (I find them cheap at big box home improvement stores) with an output = volume of fish tank/1 hr. For example, in your 300 gallon system, if the fish tank is 250 gallons, the pump should have an output of about 250 gallons per hour (gph). Larger is fine, but more expensive, and smaller will be probably be ok most of the time, but it can lead to poor water quality for the fish if the system is heavily stocked or they are fed heavily.

      For heaters in a system of that size, I would say to get an aquarium heater (or two) from the pet store (don’t get the cheapest, it probably won’t work well). For information on how to calculate how powerful of a heater you need, visit this website. I wouldn’t recommend buying things from this company as they are typically overpriced, but the products are usually good quality.

  8. IMHO 50 gallon Rubbermaid stock tanks are the bomb as a flood and drain grow bed. Haven’t personal tried them for deep water, but I see no issues there either.

    • I use them for mini ponds for the geese and ducks and I have to say they are damn well bullet proof!

      They make ones that are I think 100 gallons, deeper and not much more money. Those ones also are pre drilled and tapped for a drain hole, I think they might be better for deep water.

    • I would agree. They are water tight, agriculture safe, and relatively cheap = a great material!

  9. I built mine on top of an old stock tank 10 ft round by 2 ft. put planks on top of the tank and a bunch of homemade dutch buckets and pumped the water up and let it drain down one hour on on hour off 24/7 . lots of good veggies green peppers,tomato’s, sweet peppers etc.

    threw a couple alge eaters in the mix to keep the tank clean. before the killing freeze the alge eaters where about 10 inches long.

    I’ve had tilipia die twice. moving to catfish next time

    Heres a short video about it. the dutch bucket system is shown at the end. By the way the revised system did not work nearly as well ass the dutch bucket version.

  10. Just a quick not for Australian listeners.

    Talapia are illegal in most states in Australia. It is regarded as a pest and large fines (up to $11k in NSW) can be imposed if caught breeding or selling Talapia. They can be used but written permission, permits and audits could be applied. Here is what NSW Dept of Primary Industries says :

    Please check with your local Dept of Fisheries, or Primary Industries.

    Fish commonly used in aquaponics and aquaculture systems in Australia include jade and silver perch, barramundi, murray and sleepy cod. Yabbies are a commonly used crayfish.

    Thanks for another great podcast Jack and Tom.

  11. Can any of the hydroponic growbed methods be used. there is a method called graval flow, that are long ditches angled at 3°, lined with pondliner and emptying into sumptanks. wil it work for aquaponics, or will it clog up.

  12. My dream in my cold climate is too have a couple acre perch pond with geese in it. Geese would provide nutrient source for increased food base for minnows and if nutrients were too high pump water into cattail bed to absorb excess. Don’t know if would be possible to vacuum bottom to get rid of excess waste products (that too would be pumped into cattail bed) and returned to pond? I know that perch are slower growers but they have higher yield that bluegills. I don’t know effectiveness of cattail bed of managing ammonia either. Would be fun.