Backyard Aquaponics
A place to discuss aquaponics

My biggest issue Is that I really just need to expand my market considerably. And this isn't the time of year to do it since it is hard to keep the produce quality top notch in the heat and a good % of the population isn't here this time of year.

Yeah, this is a good time to clean the gardens/greenhouses out and get ready for planting season.

If Catfish are tricky to sell small scale, have you thought about raising and selling ornamental fish? Something like Koi? Or fancy goldfish? Both will breed easily enough in tank culture, and aren't too tricky to raise from fry.

And at least in Australia, both are fricking expensive to buy.

there are lots of people doing ornamental fish in FL, to get good money you tend to have to put quite a bit into the breeding. Ryan already does this but I haven't done any research into it. I like to eat catfish.

Congrats, keep the updates coming.

emp1953
http://www.backyardaquaponics.com/forum/viewtopic.php?f=18&t=22925

This is probably worthy of a thread over in Useful info or something.

RAFT BED CLEANING!!!!!!!!!!!

UGH.
I know so many of the proponents of the use raft beds because the gravel will need washing camp spend so much time harping on about having to wash the gravel. BUT they never mention that you have to clean out your raft beds yearly!!!!!!!!!!

I've only ever washed gravel for aquaponics ONCE and never re-washed it after any particular period of time. See there are worms that live in the gravel and if a bed reaches the point of root clogging or even fish poo clogging, I just let the bed rest for a time and let the worms work on it. I've never had to pull all the gravel out to re-wash it. (I've only done that in a duck system and that is just because of all the sand and dirt the ducks and chickens scratched up into the gravel!!!)))))))

Now that I've been running some raft beds for a few years, I've found that about once a year they need a good clean out. I don't believe this is due to solids coming from the fish tanks so much. It seems to be more from what is growing in and falling into the raft beds. My system is outdoors so some leaves and stuff blow into the system. However, probably more problematic is the debris that come directly from the things growing in the rafts and the algae that manages to grow around the edges or in gaps. Plants will naturally have some amount of roots that die off over the growing cycle, some types of plants do this a lot more than others and it will be more severe under different circumstances, these root bits become detritus in the beds and break down. Also, loose media in the net pots or whatever the growing container is will escape into the beds, especially when directly over a bubbler. I don't have too much trouble with escaping media because the peat pellets I use for some plants tend to contain it fairly well and the grow grips don't have loose media to escape. Finally, any leaves from the growing plants that fall often wind up in the beds along with frass or dead bugs. I usually pull my rafts out of the beds to wash them but any operations that leave rafts in place for washing are likely to have even more detritus make it down into the beds.

Eventually all this detritus in the raft beds means you eventually need to do a big clean out and I don't think going much more than a year between clean outs is good.

This is somewhat disruptive to planting/harvesting schedules because it usually means a bed has to go at least a day or so offline so production is likely to take a hit for at least a week if there is more than one bed to do.
Anyway, we do our cleaning during the summer when planting schedules have to be short anyway since lettuce will bolt if left too long and pick a week to start the cleaning operations and we harvest an extra bed to start but don't re-plant it. Once we have a bed empty we get started.
So my method for clean out has been to stick tall stand pipes in the bed to be cleaned and divert flow so it doesn't need to go through that bed for a time. I shut off the air to that bed and pull the air stones to soak in H2O2. I then pump out most of the water from the bed.
Then I start using the big wet/dry shop vac to suck out the rest of the water and gunk.
I have a choice to use the gunky water in the soil beds or wicking beds or I can de-water the gunk to put in the worm bins (the worms love the stuff.) I think I usually have to empty the big vac 4-6 times when cleaning a 4' by 20' raft bed depending on if I need to add any water while cleaning off the sides.

I then have to partially pump down the next bed over and get the air stones back in, move the rafts from the next bed over and finish the switch over of flow so I can pump down the next bed and clean that one.

I've searched for descriptions of how others go about cleaning out raft beds in big operations but have found NOTHING in my searching. I've posted the question a few times and for the most part I've gotten answers like Oh that's how I did it (shop vac) or some vague notion of a modified swimming pool vac without much description of how to manage it. Several people told me to put a drain in the bottom of the raft bed (not sure how that helps, I already have a drain in the bottom, but it goes to the sump so I would just be pumping all the gunk back around the system or I would need to shut down everything in order to run the shop vac just in the sump while the fish are without circulation and filtration. And trying to wash everything into the drain would just mean needing to waste more water to get it done. At least in my system when I'm cleaning the small raft beds I don't loose any water from the system because I can handle that amount of fluctuation. It is only when I have to empty the BIG one that loose water or need a temporary storage location.

Looking for ideas for cleaning. I'm wondering if anyone has come up with an airlift sort of "bed vac"? The idea has been rattling around in my head. I have air lines next to each bed so would be easy on the plumbing part. Maybe something akin to the venturi hand held pool sweeper but without the need to run a hose which would be adding undesirable water into the system. I don't really want to set up another pump that is strong enough to run hose pressure to do the venturi thing without adding extra water (and it means dragging around big heavy hoses for something that is in my experience only marginally effective at removing the fine settled solids.) Only question is would the airlift idea be able to do it any more effectively?

I think I'll duplicate this post in a new thread so people can play with the idea.
Done http://www.backyardaquaponics.com/forum/viewtopic.php?f=11&t=25609

Ask Ryan. I know he's been cleaning his dwc beds this week.

Why don't you put a bucket under the disconnected drain and push the solids into it, that works for my 1.2 sqm raft? I just drain enough water before it starts flushing solids into the sump and than divert actually into a watering can and apply onto the dirt garden.

My raft beds are on the ground and the smallest one holds over 500 gallons of water.

Ugh I've been terrible about keeping up with updates.

Anyway, all the raft beds got cleaned out and we harvested lots of fish and moved fish around.
As of a few weeks ago we had gotten 100 new fingerlings in the quarantine system
We had 49 Fish in the tank on the media bed system
We had 40 fish in the indoor tank on the Raft/tower system and 30 fish in the remote tank on that same system.

And then we had a backup failure the same night as a heavy rain and the weather was HOT HOT. The failure was only on the Raft/tower system but at this point I think there may only be 3 fish left out in the remote tank. The Inside tank was a complete kill right away the remote tank had a little bit of air so only a third of them were floating quickly and over the next week we lost most of the rest of them.

So the Tower/Raft system is running almost fishless. I'm putting fish feed into the mineralization tank and then dosing the system with the clear water from that but I'm sure the system is way low on nutrients since I didn't start doing that right away since I had to let the system recover from such a load of dead slimy huge fish. (Our compost bin got a huge overdrive boost from probably 200 lb of fish, sorry no I didn't weight them, it was bad enough having to lift them twice.)

On a bright note, started mixing sifted worm castings with the just coir for starting seedlings and MAN this batch of seedlings looks Awsome!!!! I just have to contend with some volunteers showing up in the tray.

Another Bright note. We have started on cool room construction. Back when I insulated the ceiling of the addition here, I had to get twice as much of the Thermax foam as I needed just to be able to order the stuff, so I've had this metal coated foam in storage and finally I'm using it to build the cool room. We cleared out one of the stalls and have started making the floor. The materials are all on site and I expect we might have it built or mostly finished by the end of the week.

Perhaps tomorrow during nap time I'll manage to post pictures.

Sounds good TC. Sorry about the fish. That sucks.

Yeah sorry you lost fish TC. I hope the system recovery is quick.

System still functioning all right, just a bit of a dip in nutrient.

What sucked was hauling all the dead nasty slimy fish out. Who knew they could get so nasty so fast, it was just overnight!

Pictures!

Those seedlings I mentioned


And getting the cool room built.

TC, What is the base of the pavers? it looks like foam? I've laid a whole lot of pavers, but never seen foam as a base. We always use crushed concrete. 416.00 a ton, and compacts better then limerock. Also we don't use sand over the top of the base, just screed the base out and lay. Then run over with plate compacter, sand and repeat. Also, the 4 x 8" size is actually faster to lay then the 12 x 12. They're much lighter and you can stage more brick quicker and keep the installer(s) working. I'm talking doing hundreds of feet a day, so not as important in a small area.

Looks good.