Backyard Aquaponics
A place to discuss aquaponics

A friend in Virginia has a medium size flood and drain system (presently not running due to his illness) that, when he first started, was outside -- he couldn't afford a greenhouse.

He noticed after a few months operation that there was a large population of earth worms in the beds. At the end of the season he shut his system down and left it uncovered for the winter and noticed in the spring the worms were still there. He reckoned, the worms got there from the droppings of birds.

Seemingly, the benefit of the worms was that they took care of any waste solids. He reasoned that the worms where converting the solids to something the plants could use.

Does anyone else here have experience with such worms?

Thanks,

Jim

Many people actually put composting worms into their gravel beds.

Worms could also have gotten there from transplants if there was still a little bit of dirt/compost/potting mix clinging to the roots. baby worms and cocoons are sometimes very hard to see and easy to miss.

I don't really expect that many worms survive a transit through a bird's digestive tract.

It is also possible that if the grow beds are close to the ground and any mulch (leaves) piled up next to the bed, the worms got in there on their own. Worms will often find their way into leaves or under leaves where ever they collect.

Yes, worms are a wonderful part of the aquaponic eco system. They help take care of excess solids and their castings have all sorts of great properties. My fish also like eating worms but I wouldn't want to harvest worms from the grow beds for the fish. We have other worm bins for that.

My question is at what point to add the worms. I have worm bins I can pull from, just now sure how soon the system can support/benefit from the addition of the worms?

I would say worms are not only ok, but necessary .

I have trialled worms in one row of my growbeds, left the other row alone. I want to see the difference I added them from the start.

worms will colonize to the amount of food available, so you can put them in at the same time as the fish, they would start on the fish poo and increase in numbers as the food increases.

I think vb started with less than a dozen and now counts them by the kilo

One thing I have noticed is that worms do a lot better in the gravel bed than the expanded clay ball one. They do however still live in the clay ball one - just don't seem to colonise as well.

I also put some castings into my beds so the plants can get some benefits even before the worms really take hold. I just put a small bit of castings under the water inlet to the bed so they would be washed into the bed. I waited till I had harvested my first plant before I put any worms into the pee ponic system beds. I have not yet put any worms into the big system beds but I probably will soon.

So then, my supposition that the worms eat the solid waste(poo) and release something that is usable directly by the plants?

I received a copy of a manual from the Freshwater Institute on an aquaponic system they designed and ran. But it had a filtration system that took all the solid waste out before the beds (they apparently didn't have worms). Presumably they just discarded it. They had 880 gallons of water and up to around 400 pounds of fish at one time, but only 4 4x8 gravel beds.

The only thing I could guess was that fish, and not plant life, was their focus, because they wasted a lot of the nutrient.

Jim

Jim - many of the big commercial operations filter the solids out as you have said. One reason for this is that they use deep water culture for growing their plants, and for this the water must be free of solids, which would otherwise attach to the roots and end up floating on top of the water also. This method of removing solids also reduces significantly (for obvious reasons) the amount of ammonia being converted to nitrite and on to nitrate and therefore the amount of biofiltreation needed and the amount of plants needed to remove nitrate. While I would stop short of saying that the plants are a by product for these operations (given that some of them produce heaps of them and will still make more money from the plants than the fish) - on balance they have more fish to plants than our types of systems.

Any thought giving to the build up of worm castings..Will they just breakdown and add their nutrients to the system??

Yep - makes worm tea

I have to wait for the rains to get worms for my system - only about 2 months away now.

You could always mail order composting worms if you lack vitamin P

I bet ya you find them in both beds at the end of the trial.

With worm castings i recon they will leach all their goodness out and you will be left with an inert addition to your medai much like humus (A dark colored, stable form of organic matter that remains after most of plant or animal residues have decomposed.) Which incidentally many soils are lacking