Backyard Aquaponics
A place to discuss aquaponics

Using the spent grains from the mashturn sounds like a good idea.
Could the yeast be heat killed to stop fouling the water and still be beneficial as fish food.
Are there any vegies that would improve the nutritional value of the pellet.
Could gelatin be used as a binding agent.
Darren

I make 15 gal batch of beer all the time and I buy my malted barley from a brewery. I could get a truck load of spent grain and yeast trub from them too. As far as making it into a fish food, what about using gelatin?
Mix the grain, yeast trub with a little water and gelatin and refrigerate it in trays about 1/2" thick. Slice it into smaller pieces with a butter knife and throw it in.

I used to make my own fish food for my salt water aquarium years ago.
I would blend shrimp, fish and peas or green beans. I would add a little gelatin and put the mush in plastic bags and freeze it. I would seal the bag and have just enough in it so it would flatten out to about 1/4" thick.
It would freeze into a flat slab of fish food. I could just cut a piece off each day and feed it to the fish. It would float on the surface and the fish would attack it until it was all gone.

I'm glad there are so many other brewers on here. I'm stoked about using spent grains and dumped yeast for food. I'll be checking this thread often.

While not directly related, what about the byproduct from making home made alcohol uasing sugar and yeast in water?

There would still be a lot of unconverted sugar and the spent yeast. After distilling, would the mash be of any use in aquaponics.

It seems such a shame to dump it.

Tony

I wonder if the small minnows will eat the yeast up. I could raise the minniws on the yeast trub and feed them to my bluegill. It is getting more complicated now...

FREE FOOD
I like the idea of gringing up worms (from my grow bed), Black Soldier Flys (grown from table scraps), and mixing that with spent grain and the yeast slurry, then freeze it in slabs about an inch thick, then bust it up and keep it frozen on chunks in a bucket.

That is basicly free food for my fish, because I will get about 20 gallons of yeast slurry and spent grain from a local brewery. And a good friend of mine who records BrewCrAzY with me is starting a brewery very close "Gulf Coast Brewing Co."

FYI He is on the Homebrew Talk Forum all the time, not sure that his name on the forum is...

You guys want to put Vegemite out of business??? I say eat the brewers yeast as vegemite and that gives you the energy to look after the fish:)

Is that all Vegemite is? I have never seen the stuff, must be a Australian thing.

Fish, like all animal life forms... need diets that are balanced for optimal growth... and protein and muscle formation (flesh) is determined by essential amino and fatty acids...

The other essential component of fish feed diets is trace elements...

This is really interesting stuff...

I first got into aquaponics in an effort to make my food supply more sustainable and reduce our household "footprint", but have since discovered that the fish food I'm feeding my trout is probably 60% fishmeal from wild-caught fish, thereby contributing to the problem of overfishing! So much for improving my food sustainability.

I think in future I will opt for a fish species that can survive on a lower protein diet than my rainbow trout (which are carnivorous and hence require a high-fish diet). This means going for e.g. Silver Perch. But they will still need a relatively high protein diet. I have thought that a combination of vegetable-based feed pellets and home-grown worms (fed with manure from other animals, e.g. chooks & ducks, maybe eventually a goat) may be a workable solution for me (quarter acre country block), but it greatly increases the work involved in the system, and anyway this is impossible in an urban aquaponics setup where there's no room for the other animals to contribute.

It seems that if urban aquaponics is to survive and be sustainable, the feed issue needs to be resolved. Beer-making waste sounds like it would provide a suitably large high protein waste-stream to be tapped. I wonder how large it is? I like the thought of aquaponics growing so large it competes with Vegemite! Imagine! This would simply increase the demand for beer

SARDI have an aquaculture research facility containing an experimental feed extrusion machine, that may be of help:
http://www.sardi.sa.gov.au/about_us_2/f ... on_centre2

They apparently will do small runs (as little as 100kg) for R&D purposes. If a few of us banded together, and if we got the beer waste for almost nothing, then it might be possible to fund a small batch. Once they have the settings right, I believe they can run subsequent batches more cheaply. Or, if it worked, then that could be such a good "proof of concept" that somebody sets up a backyard feed-mill supplying the rest of us with beer-based feed!

I think it would be worth contacting SARDI and finding out whether they are interested in helping.

Beer / brewery dregs have been used for decades if not longer as fish/animal feed.

This one looks cool:

http://www.onsitefeedmill.com/Find%20Out%20More/Find%20out%20more.htm

Its scary that there is a chappo on here as well

Chappo on aussiehomebrewer.com is from qld

I brew all grain beer and my chooks and worms get some of the spent grain and the compost bin the rest. Will definetely try some with the fish when I get some.

I reckon the spent Grain could be alright to feed the fish (if they eat it) Im sure the Barra Im getting wont be interested. At the moment the Chooks get the spent grain.
I mainly use a Pale Crystal Grain for my Ales. But I also use a fair bit of Roasted Barley Grain for my Stouts to get that nice burnt sticks flavour as the wife puts it.

Im not sure on using the trub as it will have unfermentable sugars (unless using Dextrose), yeast, hops and Alcohol in it. I think it would probably lead to tank pollution more than anything.

Cheers & Beers

I wouldnt put the trub near plants even and never near fish. The kettle trub goes down the gully trap. Spent yeast cake from fermenters might be ok but messy

edit: read your post to quickly and you were talking about the trub from the fermenter

This sounds great ! I love to brew beer, and usually tip my grains into the compost bin..
Has anyone here ACTUALLY fed their tilapia spent grains ??
How did you dry it ?
How did you store it ?
How did they like it ?

I think it is a fascinating idea, but since I haven't grown out a batch of 50 tilapia yet, I have no "constant" to base it on..

I'm not crazy about super fast growth rates.. I need to grow them out in a season (which is pretty long here) but that's about it.
I'm more interested in sustainability, and using a product i'm already discarding sounds perfect !!

If anyone has seen or tried feeding spent grains (or even fermenter trub) I'd LOVE to hear about it !!!