basic aquaponics theory?

[Brian Mouncer]

Hi,

I'm a compleate newbie, so please be patient...

I grew up on a small country farm, but moved away do do computer science.

I like gardening though and am looking into aquaponic for my urban back yard.

 

I still have one basic question not realy explained in Bernstein's Aquaponics Gardening book.

In traditional garening you compost the stalks and roots of plants you've grown, and you grow cover crops and nitrigen fixers to restore balance to the soil.

 

How do you balance an aqauponics system?  your taking out large amounts of minerals from the system, and adding back in fish food.  as the harvest goes on, I will end up with lots of plant waste and food scraps that I would usualy compost and add back into the system, how do you do this with aquaponics?  The ultimate solution would be taking the human waste and putting it back into the system too, so that it would be a "compleate cycle".  e.g. a septic system that grew fish food, that you then transfered to the fish two step filter to isolate human deseases... but I'm guessing people grow there own fish food, and ignore/compinsate for the losses going down the toilet? 

 

What and how do you grow for fish food (for this topic lets say I have trout or pirch)?

Do you have a seporate compose bin, with bugs and worms that become fish food?

For vegitarian fish, do you have a seporate bed/garden with plants the fish will eat. how do you go about processing the food you feed to the fish - grow it in the fish tank or a seporate alge tank???

 

 

Thanks,

 

Brian.

[Keith Rowan]

i have worm bins set up for waste from my ap (cuttings/removed roots etc)

scuds get cuttings as well,

i feed extra worms to the fish or put them in the growbeds to help break down solids (red wiggler, or composting worms - good idea to have a population in media growbeds)

i also grow crayfish to feed the perch - i have seen tilapia eat the crays as well.. i grow duckweed in other tanks for the tilapia, mine don't care for water lettuce..

i've also been breeding minnows, but they grow way to slow 

my "main" fish feed though, is purina game fish chow, and aquamax 5d09 for tilapia - 5d03 (i think) for the tilapia fry

i consider all the other stuff as supplemental feed to the commercial fish feed,, which will provide your plants and fish with all they need to grow well..

[Brian Mouncer]

Any way to make a compost tea, and then grow fish food plants and bugs in that.

I'm wundering if you can run a system without putting any or at least very little comercial fish food into the system?

[Sam Burton]

There are plenty of people who grow their own duckweed and feed it all year round. Most people freeze it during the summer so they can feed chunks during the other months. Also, worms, black soldier fly larvae, rabbit poo and all kinds of things have gone into cost cutting. It is very possible by using a little ingenuity.

[Brian Mouncer]

Sam Burton said:

There are plenty of people who grow their own duckweed and feed it all year round. Most people freeze it during the summer so they can feed chunks during the other months. Also, worms, black soldier fly larvae, rabbit poo and all kinds of things have gone into cost cutting. It is very possible by using a little ingenuity.

[Keith Rowan]

while there are quite a few home grown supplement feeds you can come up with, it really is best to use the correct type of fish food,,, and supplement with dw, worms, bugs etc.. your plants and fish will be happier.. a closed system will deplete itself of nutrients, if it even gets a good start

[George]

I use organic fish food and supplement with worms and black soldier fly larvae, along with any worms I see on the vegetables.  There is a forum category and groups for food that you might benefit from by reading.  I intend to expand and add crawfish and minnows.  We'll see how it goes.  I compost for worms and grow food, use scraps for BSFL.  

I planted tomatoes today, both in aquaponics and in the ground.  We've had fish in the system for 9 months and aquaponics is outperforming ground all the way around, and I'm a good conventional gardener.  Continue reading.  I think there is a group for your part of the country. 

Balance - a properly designed and stocked media system tends to stay pretty much in balance, except for perhaps PH adjustment.

Good luck.

[George]

Heck, I thought I knew stuff.  Scuds?

Keith Rowan said:

scuds get cuttings as well,

[Debra Colvin]

In the case of tilapia, apparently they eat algae. That's why I kept finding pics of chicken cages suspended over ponds.. Its a practice in 3rd world countries; the idea is to give the algae a head start before the fish keeper adds fish

[Jon Parr]

George, scuds (or gammarus) are key to Aquaponics IMO. Look them up. They are insanely good at breaking down system solids and organic leftovers into increasingly smaller particles, capable of eliminating the need for media, solids separators, and associated maintenance.

Brian, to close the loop you need the intermediate organisms. Trout and perch are carnivores, so to balance you need the herbivores and omnivores somewhere in the system as well. It would be a much shorter loop if you only had herbivores and omnivores (carp, tilapia) in the system, but certainly possible with carnivores, too. BSFL, worms, and scuds (and/or a ton of other creatures) can process everything you would otherwise compost. And if compost is your thing, them by all means do a compost based "ponics" system to grow fodder or food directly.

Depending on what you wish to eat, devise a routine for incorporating those foods/creatures in your loop. Personally, we eat a lot of meat, specifically fish, rabbit, chicken, and wild game. All of our kitchen scraps get sorted into two piles, one for chickens, and one for rabbits (rabbits also get garden stalks, weed wacking debris, prunings, brush, etc). Whatever is rejected or surplus after feeding, combined with the animal waste, goes into a BSFL bin. The BSFL directly feed fish and chickens. The casings from BSFL get fed to the worms, and the worm castings get brewed into foliar feed and insecticide. The rabbit droppings can be fed directly to tilapia or carp, after desiccation in a solar kiln to destroy pathogens. The rabbit guts, fish guts, wild game guts, etc. go back into the BSFL bin. Everything feeds something else, though there is quite an infrastructure involved to get there.

Human urine can be used in biodigesters, pee-ponics, humonia, or duckweed beds. Human feces can be used in biodigesters, BSFL, or humanure. Personally, I am content for the time being to flush the toilet and let those nutrients go through my septic system, to feed the flowers and the trees. The nutrients are not lost or even wasted. And I'm plenty busy. If you choose to truly close the loop and recycle your waste, remember what else goes into your sewer, soaps, bleach, pathogens, chemicals, etc. If you remove the human waste from sewer, you concentrate the rest, and remove the biotics (carbohydrates and nitrogen) required to break it all down. Good luck.

[Brian Mouncer]

I'm less interested in closing the loop, and more into cresting a gatden that is not reliant on commercial fish food or fertelizers....

[Brian Mouncer]

Scuds and BSFL sound promising. Do you grow them in the same yank as the fish, a separate tank in the same system, or in a separate tank and bed?

 

Thanks for such a detailed reply.

Do you have blog or page following your system setup???

[Jon Parr]

My personal ideal AP system is evolving with new info, but currently I have an SLO on a 1000 gal FT, gravity flow to the bottom of a 55 gal barrel filled with bird netting, that top overflows to raft beds (160 sq ft and growing, now building a 5400 sq ft commercial layout), which is pumped back to FT. The scuds live primarily in the bird netting, but will drift everywhere in the system. I will add a few red ear sunfish to the rafts to eat the scuds that end up there, as I will be selling the produce alive and bare root, and people get freaked out by critters. If they make it back to the FT, then the fish eat them. The bird netting traps the poo and gives structure for the scuds. The BSFL is a separate bin, placed above the FT, and when they self harvest, they simply drop into the water where various sunfish await them. I also have a BSFL bin in the chicken coop. When they self harvest at night while the chickens are roosting, they get away to perpetuate the species. When they leave the bin in the daylight, they don't stand a chance. The biopod is a commercially sold unit, but they are easy to make on your own.

Here's a video of a commercial system I shot in San Diego that shows scuds. http://www.youtube.com/watch?v=NRkxMvbLAxg&feature=youtube_gdat...

I'm in the process of building a website, I'll keep you posted when it's launched.