Backyard Aquaponics
A place to discuss aquaponics

Since duckweed doesn't require much depth, I made up this thing where layers of clear (glass?) trays and some lights could give you a lot of surface area in a small volume. I might play with something like this in the Winter when I have to do things indoors.

Impressive... love to hear how it works out!

You just made that up Dave.....? You don't muck around do you....

That is clever! Real slick!

I like the idea of the duckweed stack. It's similar to the cabinets that they use to turn grain into hydroponic fodder and, provided you keep the temperature right, I can't see why it wouldn't work well.

Very nice.

What's duckweed light/heat requirements? May have sparked a hybrid idea here but I'm still a bit green on my duckweed skills.

AA gary posted a topic about optimum duckweed growth parameters somewhere

Power consumption v/s production... is it energy effecient?

Can't find a picture of a "worm gin" (there is a brief clip on this movie where you can see one), but it is like that, except using water instead of conveyor belts.

http://www.terracycle.ca/story.htm

They sell this liquid worm compost product at WalMart apparently - that's a big deal here as everyone in the US can easily buy worm compost in a bottle now.

your own worm farm makes the the same stuff and you can buy it here too, it is just called orgainic liquid...
you can read about it briefly here (they do not seem to have their own web site!) http://www1.auspost.com.au/priority/ind ... cle_id=234

I don't really get (understand) this conversation?

U talking about worm farms?

If so that is easy!

EASY!


What's the problem? (Be Precise!)

Then we can get an answer to you ASAP!

I don't have a worm farm - tried keeping some in a tub a few years ago but it got too moist and they ran away! I do have a compost bin and was really happy that I produced enough to cover my vegetables with it this year.

I am not saying that worm farms are hard, just that having this stuff available at WalMart in a bottle no muss no fuss lowers all barriers to people using organic methods on their houseplants. The alternative is MiracleGro, which is the devil. I am impressed that worm compost tea is now available in over 7,000 stores, in every town.

"According to one of Queensland`s new-generation worm farmers, whose entire _direct-mail_ business hinges on keeping about five billion worms happy each day, these slippery little critters are "temperamental, fussy and very intelligent". "

You could get this stuff direct mail for years before from smaller producers, but I'm excited that it has gone mainstream here. It is like 15 years ago nowhere in my area had cappucinos or lattes, and now today everyone does and it is good... (I need coffee!)

I am worried that you could keep this device from becoming an algae stack instead of a duckweed stack.

Is there some way to promote duckweed and at the same time discourage algae growth?

I'm not sure that there is Dave.

Uou'll have to try it and see. Duckweed i think inhibit algae growth by blocking the light by forming a cover over the water. in your example the light is from the sides. However EB has stated that the water in uncycled aquaponics systems is very green, and tend to clear up once everything is in ballance, so with the duckweed competing (strongly) for the nutes you may be OK. Looks like you already have the test unit set up, give it a go and keep us posted. I'd use water from your main system as the source of nutes. Maybe change it every second day. If this set up works it may be a good nutrient extraction / feed producer crop for when you winterise your system inside?

Heh, no, this is just a rendered CAD model... I am going to look around for some kind of very clear plastic trays to use - plastic so a hole can be cut in it for the drain. I imagine the tray racks used in restaurants would be a ready-made solution too.