Backyard Aquaponics
A place to discuss aquaponics

Charcoal? That's crazy!

Thanks, Dave. Nice to learn more about the company I keep.

It's looking excellent, Jimbo!!! Beautiful stands, and the piping through the IBC is really neat, too.
I have started my own thread, and here is the link:
http://www.backyardaquaponics.com/forum/viewtopic.php?f=18&t=12019&p=319544#p319544

Might do more experimentation with the next system, but at the moment, we're happy making this one work. Fish soon, I hope!

"Okay, Dave. How long does it take for the charcoal to saturate and quit floating?" he asked as chunks fell over the edge of the growbed.
I got enough charcoal to finish filling, encouraged some settling with the tamp, and started filling the system with water. Yes, charcoal floats. So, I'm still about 3-4" from getting the system to its full running height. Need to wait for it to soak up some water and settle back down. I went ahead and started the airlift and it is circulating a little water at the higher head. Guessing its about half of what it does at designed head.
I'll check on things tomorrow and hopefully have a couple of settled growbeds so that I can start some planting.


The top of the charcoal was below the sides of the growbed and standpipe by an inch or so, before starting to fill with water. And the plumbing is not finished yet-please don't judge too harshly with the undersized tee,etc.
Now who wants to see some hot chicks?

Ack, I wish I read about this using charcoal for the flooded beds before now!

I've never actually run flood and drain with my charcoal, it's always been either in net pots in a DWC trough or more of a constant flow with little flood height. The charcoal in the trash can filter was flooded though. There was probably a foot or maybe a little less of "dry" or moist charcoal on the top after the drain pipe, to hold the other floating charcoal down.

When charcoal is flooded it makes a kind of slurry, which might not be a great support for the plants.

The larger the chunks the more and longer they will float. If you can break them up (occasionally over time, I know it takes awhile to break them up I don't have a great automatic way to do it, have run them over with the car but that makes a lot of dust, I didn't have too much to break up before so I used channel lock pliers and my hands to break them down) then they will sink. But even sinking they are practically neutrally buoyant.

The front trough in my greenhouse is full of charcoal, but that is a kind of trickle bed, it's fed continuously with just a short section of pipe on the drain to set the height maybe 1/3 up. Charcoal wicks water pretty well actually so only the topmost surface of it is dry in that trough.

This will be a constantly flooded setup sooooo I'll be patient. Even if I get to neutral bouyancy, that's better than crawling over the sides. I did some crunching while in the bag. And the rinsing took place in the growbeds and out to the lawn. You can probably see there's still alot of big chunks.
I guess we'll see what's there in the morning.

Extremely sturdy. I would happily jump up and down on my grow beds whilst simultaneously sleeping under them.

My blue barrels sit on a wooden frame stretching across 3 crates.

The 4 x 50 cent buckets I used before were not so sturdy

I'm almost convinced you could somehow manage to do this. Maybe being in 2 places at once can be thing number 97 on your list.

Well I did manage to warp space, and put an IBC and two extra grow beds in my 1.8m x 1.8m growhouse and still have room left over, so how hard could it be

Regarding the chunks breaking up, keep watering them and over time they can be easy to break up, from time to time I squeeze the remaining large pieces and they split easily sometimes. Easier than when they were new. I think temp swings and wet versus dry state helps to fracture them.

Also I'm curious how your pH will do, some people think charcoal would cause a high pH but I think that may be only due to ash. My pH has been high but I don't know if that is because of the charcoal or not. My indoor aquarium is also using a trickle charcoal bed thing and if I can get some time I'll check the pH for both and see where it's at.

My pH is probably going to start out around 8 because of my well water. As soon as I get to a working water height, I have a couple of spare pieces of driftwood to throw in the FT and can always pull one or two more out of my aquariums to start bringing it down. I also have some Fluval peat pellets I can put in a sock to help out.

Definite progress! The charcoal has visibly settled since yesterday but the whole mass still has a little float to it. I press down an area with the tamp and don't get as much rebound as I did previously. Maybe another day or two and planting can begin.

But, if it doesn't settle out soon, maybe I'll get some plastic hardware cloth and make the top 3-4" layer gravel. Or I should quit obsessing and wait.

Hmm...to stop obsessing? Easier said than done. I planted seeds a week ago, I practically sit and watch all day for signs of life...
I was wondering about high pH of charcoal, too. I wouldn't put wood ash on our blueberries, but maybe charcoal is different? Nice and light, anyway!

I wonder if 50c buckets filled with concrete could be stands?

a 50cent bucket filled with almost anything would work. (Everything except air (my structural re-enforcing media of choice))

Although even air worked for me for 6 months until I upgraded to milk crates