Backyard Aquaponics
A place to discuss aquaponics

I ripped out one of my gravel growbeds today to replant with an experimental crop of basil. After removing all of the plants I thought I would check out the issues of clogging in the gravel as there has been a fair amount of discussion over time about the subject.

The system (my large flood and drain) has been running for about two and a half years now, with all solids being pumped straight into the gravel growbeds. Also I tend to leave plants in the system for quite some time and they produce very extensive root systems that don't all get pulled out when you remove the plant, so I expected there to be a fair amount of gunk deep in the gravel.

I dug all the way to the bottom of the grow bed and the gravel was unbelievably clean.... . Amazingly clean, there was practically no particulate matter amongst the gravel at all.. There were a few fresh broken roots of the plants that I had just removed, but so far as old rotting roots and plant matter, or solids from the fish tank, there was nothing.... I even dug in another spot just to be sure that I hadn't happened upon the one clean spot in the bed, same thing, clean as a whistle....

Go, you flood and drain gravel beds......

EB, Did you find any worms ? I think I recall you saying once before that earth worms had taken up residence in one of your grow beds ?
Great to put to rest the voices that say the gravel is not the best way to go !!

Muzza

Yep, found a few worms, as well as what seemed to be two worms mating, if they do..... It was two worms sort of stuck together.....

Take any pictures :sign12:

Good to hear EB. Must admit I was a bit worried when the 'experts' from overseas started saying that gravel does not work. The proof is in the pudding.

Nioce work, when I saw the thread title, you had me worried, but if it hasn't clogged after 2 or more years and the system is mature and the ecosystem is rocking along, I can't see why it would ever clog. Reinforces your idea that gravel beds are the go for doubling as grow media and biofilter- simple!!

Great find Joel. And thanks for posting it up. Do you think that maybe the worms ate the old plant roots?

Cheers,

Duncan.

great news!
What size gravel was that EB? One of our students wants to use a 6mm gravel and I thought that it MIGHT be a little bit on the small size - any ideas?

I was also worried with the title

Grat news!

RE: worms : Yes, although they have both sex organs apparently they still need a mate, they wrap around each other to mate. the "ring" that you see around them denotes a sexually mature worm........i feel bad when i feed these ones to the fish, but there are so many of them

I was actually thinking of introducing a handfull of compost worms into the gravel when the plnts are all established..........What do you think?

Give it a go - can't do any harm. Just don't add so many that it will polute the system if they all end up dying.

I added 3 or 4 to each of my little growbeds... and when I 'upgraded' the one small growbed they were still there, happy as a pig in shirt

Add the worms Steve, they like it down there, and they eat rotting roots.

My whiteworms, as I feed through the standpipe, occasionally one escapes underneath, and several days later they are on top of the scoria trying to escape. Sad to say, I just feed them back to the fish although their bid for freedom is quite impressive.

Great news on your beds Joel. A hybrid bed/dwc is a must now, got the gravel cycling in the greenhouse to start it all now.

Excellent news Joel...worms & microrganisms must be taken care of the dead roots...