Floating raft

[rfeiller]

Passion is a good thing.
Oxygen is being introduced where and how is what I'd like to know. The chemical cocktails are complex that the large growers are using. They have developed systems that apparently are industry standards in your area.
See what you can find out urbangardner, a lot of Hydroponics in my area haven't found large aquaponics.

I can understand charging for information. There was a time when people from around the world would call day or night demanding I teach them everything I knew for free so they could raise thousands of discus and become millionaire's the fact I had invested many years in developing my system didn't matter to them. When I would refuse they would become rude and angry.

[urbanfarmer]

Your right, most of the AP experts selling stuff/systems are...well, questionable. I've read enough about Friendly's set ups and have actually looked at one of their commercial set ups over in Brooksville FL. Pretty impressive.
I know the owners....I can hook you up with a free tour of the one in Brooksville...so you can check it out first hand...? Since your in the Master Gardener's program, 'maybe' they'd even let you 'sit in on' the next commercial classes in Oct.

David, that would be really great. I could not pass up an opportunity like that! As I have told many people, Friendly's training seems the most comprehensive based on their outline (click). However, I have spoken with several people that were "unimpressed" with the training and felt they did not get their money's worth. The trainings from other companies I have seen were definitely not worth the money. There's way more information on the Internet for free, and most folks would be better off joining a forum like this one to get started. On more note though, I am not saying that their system would not necessarily work. If one guy tells you to buy $5000 worth of air pumps and another guy tells you to simply life the rafts up a few inches (practically no cost) and both systems yield the same... well they both work, but in my opinion spending the $5000 is stupid in this case. A lot of these trainers may have in fact created a system that works, that I don't doubt, but they start talking about the "science" behind what and why, and they're literally blowing air out their @$$ because they really don't know, made stuff up (not to deceive anyone they think they're right), or heard something through the grapevine that's just not true. A perfect example are these "rules of thumb" regarding ratios. Most folks get told one thing or another, and the ratio only takes into consideration grow bed area and tank gallons and fails to address the fish mass and feed rate. Dr. Wilson Lennard has a tool that tackles this on his website for backyarders... ANYWAY, I hope you see what mean

[urbanfarmer]

Back to adding more air....

If the bottom of the raft isn't in the water...you lose some good surface area for the bacteria to grow on. The Dr's idea of having 2 sheets of styro, with the hole in the top one being bigger and filled with vermiculite (or was it perlite...maybe hydrotron would work too) sounds like it would be a great way to give more air to the plants ( I think he was talking about tomatoes)



here's a picture of spinach grown in a test by A.U. The left has added air...the right doesn't.

I will try to find more specific research on this as I am sure it has been done, but the farmers here in FL have tried adding air (because this is what they hear through the grapevine) and have discovered it made no difference in their yields. I mean these guys make a living off these VERY SIMPLE designs. If we slash away the crap in most systems with Occam's razor or hell just apply the K.I.S.S. principle, commercial producers can save money on initial equipment costs, maintenance, consulting and training fees, and possibly avoid other unexpected complications from complicated system designs!!!

[urbanfarmer]

Passion is a good thing.
Oxygen is being introduced where and how is what I'd like to know. The chemical cocktails are complex that the large growers are using. They have developed systems that apparently are industry standards in your area.
See what you can find out urbangardner, a lot of Hydroponics in my area haven't found large aquaponics.

Well, assuming you have a gap or some exposed surface, oxygen can enter the water there.

Also, below is not a complex chemical cocktail nor is it technologically advanced compared to anything tee hee

Add water-soluble fertilizer, such as 20-20-20 with micronutrients, at a rate of 2 teaspoons of fertilizer for each gallon of water used in the water garden. In addition, add Epsom Salts (magnesium sulfate) at a rate of one teaspoon for each gallon of water. Use a soft broom to mix the water & fertilizer in the garden or premix all fertilizer in a bucket before adding to water garden. http://edis.ifas.ufl.edu/hs184

I can understand charging for information. There was a time when people from around the world would call day or night demanding I teach them everything I knew for free so they could raise thousands of discus and become millionaire's the fact I had invested many years in developing my system didn't matter to them. When I would refuse they would become rude and angry.

You have a point... Human nature can be very ugly... I'm no Ghandi. I have no idea where we can start, but I do know that I will try to help people if I can. Obviously, as a Master Gardener I help people for free all the time, and I have experienced folks that get rude and angry because they don't get the answer the want. It's pretty unreal, but those folks are few and far between. Who knows...

[rfeiller]

i believe in helping others when given the opportunity, that is my responsibility as a human being.

the hydroponic farms in my area are considerably more complex then 20-20-20. i know of no commercial operation that uses 20-20-20. each time the solution is circulated the water is striped and new chems are automatically injected into the solution specifiically formulated for the crop being grown. total computerized lighting (natural and artificial), chem injectors, carbon dioxide, oxygen. real estate is too valuable out here to leave it to chance.

i can't imagine even a large commercial aquaponics set up not tweaking and adding nutrients that are compatible with the fish. they are in business to make money and not the business of sharing information.

[davidstcldfl]

David, that would be really great. I could not pass up an opportunity like that!

This is a tour of an organic, aquaponic commercial farm in/near Brooksville, FL....using the Friendly's set up....troughs with floating rafts.

They have free tours on the 1st and 2nd Saturday of the month. The next one will be May 7th...at 10:30. They like to have RSVP, because, they try to keep it to less then 30 people. If anyone is interested, RSVP here....(email works best, most times they are too busy to really have a chance to talk on the phone)
http://www.greenacreorganics.biz/contact_us.html

[davidstcldfl]

I started to do a little search on 'hydro' culture, since I'm not too familiar with it. Man, I didn't know there were so many sites for hydro 'cash crops'...
Now I see how it's possible 'not to' have extra air in 'static hydro'....Like U.F. said, have the roots up out of the water/nutes some by having part of the raft out of the water.
One static display I was reading about, was changing the water/solution once a week...that would keep up the DO to 'some extent'
In NFT....I found they said the plants would run out of nitrogen on 'long' runs 'before' they actually would lose DO ( on fast growing plants). On long runs, they said you could just add more nute solution at a 2nd entry point at about 1/2 ways.

So in "hydro' one can get along with out extra air.

That's what I was asking earlier....what's the difference between the 2 systems...?...Why could hydro get along without added DO ?

Since aquaponics IS different then 'hydro' the same guidelines won't always apply to both. Since AP is trying to mimic nature...we know added DO has to help the overall system. Between the fish, veggie plants and the bacteria...more DO is better.

I would still would consider Friendly's info on DO and water flow to be 'at least' a good starting point. If anyone is really 'pasionate' about this. Perhaps, do your own testing of their figures...I'd be the 1st to like to see the results.

[urbanfarmer]

OK great I will contact them. Thank you

Yes, lots to consider and more research is needed. I just want to add that I had a floating raft system with no added oxygen and the plants were doing great. I left about 2 inches of a gap between the raft and the water. I had different kinds of lettuce and 1 onion plant (just to see) (56 heads of each type of lettuce with 8x 2'x4' rafts). The reason I "had" it is because when the storms came through it damaged the foundation and then it collapsed a few weeks later. I was going to surprise you guys with the pictures and my data/research on it... Each head of lettuce was sitting in a peat pellet (which actually isn't the best, but cheap) and they were still doing fine with no root rot or signs of disease. Anyway, this was supposed to be my experiment, but it got destroyed. I will rebuild it at some point, but currently I don't have the time. I think it can work, but like you said, someone needs to at least try it long term or research needs to come out specifically for aquaponics!

[urbanfarmer]

i believe in helping others when given the opportunity, that is my responsibility as a human being.

the hydroponic farms in my area are considerably more complex then 20-20-20. i know of no commercial operation that uses 20-20-20. each time the solution is circulated the water is striped and new chems are automatically injected into the solution specifiically formulated for the crop being grown. total computerized lighting (natural and artificial), chem injectors, carbon dioxide, oxygen. real estate is too valuable out here to leave it to chance.

i can't imagine even a large commercial aquaponics set up not tweaking and adding nutrients that are compatible with the fish. they are in business to make money and not the business of sharing information.

For starters, it definitely depends on what you are growing. The examples he gave of successful small farms had no equipment running whatsoever, but they were only growing lettuce. They had the floating rafts in a greenhouse, and that's it. We didn't discuss the fertilizer in detail, but I am fairly confident they were not using anything too expensive. From a business perspective, there's no reason to increase your cost of production when there are viable alternatives that costs considerably less. With that said, I know we have all seen the hydroponic farms with all kinds of gizmos and gadgets. All I can say is that they keep it real simple down in these parts, and the restaurant Scorpio's I mentioned seems very happy with their 20-20-20 and no added oxygen setup. If the consumers like the product and the businesses are capable of producing at lower expenses, why can't that be a reality? I leave you with that thought...

[keith_r]

so is this a hydroponic site or aquaponic?

just kidding..
but, ap and hydro are completely different animals.. with fish in the mix, added oxygen is essential... it's not just about what is "sufficient" for the plants, but the what is the optimum balance..