Flow or the water

[dufflight]

I've got a few gb's with fine gravel. The worms have kept these running for almost 2 years now. I've had a dig and there are not a lot of solids but there are a lot of worms. These gb's have 40mm standpipes so the water flow is strong. I think the defination of aquaponics is still open as we are learning more all the time and there are a lot of different ways to utilize elements of AP. Value adding to the rest of the garden etc.
Plants take a lot of the solids out as well. You only have to look at pot plants and the amount of soil that gets used over time. But as JCO points out there will be a time when the gb's will need to be cleaned. I'm happy to clean them out if they get too bad. I've even worked out a quicker way of doing it. Flood the gb and use a blunt fork to move the media around and something like a post hole digger to move the media around in the deep gb's. The water gets diverted to a filter to catch the solids or just flood the dirt garden with it.

[Oliver]

Sorry to be so late in this comment, been off line here for a while.

The media filled grow beds serve several purposes, including bio-filtration. There has been some discussion on other fora about putting fish solid waste in the grow beds. Except for a few dissenters, there is general agreement that deep (12 inches or greater) media grow beds is a good place for the fish solids to be as they break down over time, a process called mineralization.

I have found that adding heterotrophic bacteria weekly aids in this process as well as keeping my fish tank water clear. It is important to realize that heterotrophic bacteria are aerobic and will remove oxygen from your water as it circulates through the grow beds where they are doing much of their work breaking down fish solid waste. This is why I'm now adding aerators to the grow beds we build and sell. This also allows for higher fish densities.

I believe there is enough evidence from those who have had several years experience with media filled deep grow beds to show that using them to collect and process fish solid waste is viable. Those who use shallow grow beds may find that they need to clean them out regularly but again, I believe that is because they have not allowed time for them to break down due to the lack of grow bed depth and perhaps the lack of aeration.

It appears from other's experience that adding worms also aid in this process. With or without worms, the byproducts still have to be mineralized and this is done by heterotrophic bacteria. Heterotrophic bacteria can be purchased on-line or at Wal Mart under the name Stress Zyme.

Oliver

[JCO]

Oliver, I read your post and swore I would not say anything and signed off the forum, but my conscience wouldn't let me get away with that. For better or worse, I am Irish and have never run from anything in my life even though Badflash says that I should just take two aspirins and call him in the morning sometimes.

Aquaponics can be done in any manner a person chooses with a modicum of success as can dirt gardening. There is no law or Sheriff that is going to come to your house to arrest you for wondering from the path, however there is a specific way in which a model Aquaponics system should be set up and that system has a sump between the F/T and the Growbeds to collect the solids to prevent them from going into the grow bed media.

If this is not done, sooner or later, even with worms in the beds, you are going to experience reduced water flow and after that you will be growing your plants in mud. It may take awhile but it is enviable. Solids can not be broken down into a liquid unless the solids are reduced in size to the point they are not visible to the eye, but sooner or later they will gather somewhere and probably where you don't want them, then it's system shut down time and yuck to clean up.


It's great to try to build a better mouse trap, but I think I am safe in saying no one has improved significantly on the original wire and spring mouse trap so far... so it goes with Aquaponics, the standard setup is the only true way of doing things and the large scale commercial operations have tried everything you can think of to improve on it, but the basics are still the standard and that's what you will find 99% of the time where ever you go with the commercial growers!

Now, it's two aspirins and off to bed and finished with this thread....(maybe)

[Oliver]

JCO wrote:

Aquaponics can be done in any manner a person chooses with a modicum of success as can dirt gardening

There indeed are a number of ways to do aquaponics as long as it is a connected recirculated aquaculture system that uses the plants as part of the water filtering process.

There is no law or Sheriff that is going to come to your house to arrest you for wondering from the path, however there is a specific way in which a model Aquaponics system should be set up and that system has a sump between the F/T and the Growbeds to collect the solids to prevent them from going into the grow bed media.

You just contradicted yourself here.

If this is not done, sooner or later, even with worms in the beds, you are going to experience reduced water flow

Reduced flow where? What part of my aquaponics system will have reduced flow?

Solids can not be broken down into a liquid unless the solids are reduced in size to the point they are not visible to the eye

Yes and no. Perhaps you should do some research on what is known as mineralization +aquaponics. It is the breaking down of solids by living organisms, with or without worms and bacteria. After it is broken down, it is "reduced in size to the point they are not visible to the eye." It is then part of what plants uptake.

the large scale commercial operations have tried everything you can think of to improve on it, but the basics are still the standard and that's what you will find 99% of the time where ever you go with the commercial growers!

I think not. What "large scale commercial operations" are you referring to here? Are talking about fish farming? This argument is getting a little old. It is like saying NASA uses rockets to go into space so why should airplanes have wings?

"Commercial" aquaponics operators (whoever they are) are not even doing the same type of aquaponics as are the backyard folks. They (hypothetically) don't even use deep media grow beds and therefore must remove solids from their high density fish growing systems. They are mainly fish based aquaculture systems that have added some grow beds to help uptake some of the nitrates, reduce the amount of water exchange and produce a secondary crop. They do not have closed balanced systems as this would not be a profitable way in which to operate (although it is possible but not the way it is currently being attempted). So the comparison in the debate is moot.

To design a backyard deep media grow bed system following that model would be a mistake as it would require components that are completely unnecessary.

Lots of progress has been made in low density backyard DIY aquaponics since Rakocy started his system and he remains the expert in his own backyard. But people going into backyard DIY aquaponics need to move on to what is best for that type of system and move away from the old ideas of the joined marriage of aquaculture and hydroponics, for that is no longer what it is about. Only the word aquaponics is about that joining those two words.

Real aquaponics is about a single connected, balanced, closed loop recirculating system that contains fish, bacteria that break down the fish wastes (both liquid and solid), maybe some worms and plants. The only things that are added are water, fish food and some minerals as needed. The only thing that is removed are the vegetables and fish.

Oliver

[badflash]

Lets call a time out with you guys, OK? You are both obviously passionate about your feelings. Lots of good points, let me make a few others.

Large commercial operations concentrate on rafting and growing plants that can grow with the roots submerged. For this to work, the solids need to be removed or they will remove the oxygen from the water and breed bacteria. Fast growing greens are just about all they grow.

Flood & drain is an entirely different animal. It has higher levels of oxygen and higher turbulence. As long as the bed media is course enough, it won't clog. Material may pass through and return to the fish tank over & over. For tilapia, this isn't a big issue as long as the turbidity doesn't get too high. They re-eat the stuff and break it down further. Plants take up most of it, and worms can break it down further as well. These systems must be monitored and guarded against over feeding. Happily, you can stop feeding for a few days and the system will usually self correct.

No system is perfect and if you add feed, you will need to do some house cleaning now & then. If your beds are sized right, it will be years before you have to break down a bed and clean it. Sadly, on a small scale we have never built a closed loop system that allows you to remove food, so you need to add, take out, and periodically clean.

[rfeiller]

which is the correct application or implimentation, i think my focus would be on which system produces the most nutrition, and the strongest healthiest plants. since most veggies have a limited life span anyway i would think cleaning out old roots and sediment would be part of the husbandry. speaking as a person with very limited experience with "ponics" of any type.

[urbanfarmer]

which is the correct application or implimentation, i think my focus would be on which system produces the most nutrition, and the strongest healthiest plants. since most veggies have a limited life span anyway i would think cleaning out old roots and sediment would be part of the husbandry. speaking as a person with very limited experience with "ponics" of any type.

The correct implementation depends on what you are doing. If you read through the posts as they debated their sides, some interesting fallacies developed, but badlfash was quick to interject and clarify those false assumptions.

You can use Oliver's flood and drain design concepts for your backyard Aquaponic system. The idea is that you do not need a sump, and the grow bed acts as both bio-filtration and mechanical filtration with minimal to no maintenance because of the mineralization of solids. Bacteria and even worms perform the bulk of this work. I have one set up like this, and it has been going strong for some time.

Also, I plan to set up a much larger system as a pilot for a commercial system. The grow beds will be floating raft (DWC, deep water culture), and I intend to stick with JCO's design concepts. However, I am toying with the idea of using gravel grow beds as part of the bio-filtration and solid removal. Naturally, there will be a sump first to remove the bulk of solids, but in case anything is missed I hope the gravel grow beds will catch them and provide a near maintenance-free mechanical filtration. There will be worms, and this is where I plan to place plant refuse to supplement nutrients. Part of the reason is to stay "organic", but I have yet to finish my research on that side of it.

Lastly, I want to tank everyone for all the wonderful information that has been presented on this forum. My knowledge has grown thanks to all of you. I think that about sumps it all up. Again, THANK YOU!

I hope that helps!