Backyard Aquaponics
A place to discuss aquaponics

Have you seen a barrelponics system? The Barrelponics manual is free to download and even if you don't build one of those systems, there is lots of useful info there. http://backyardaquaponics.com/pics/barrel-ponics.pdf

Just a couple quick notes about the barrel grow beds. If not supported up the sides a little bit, they will deform and require some help. The barrelponics manual frame uses 2 X 6 screwed to 2 X 8 to make inverted v shapes that go between and on either side of the barrel beds which seems to support them enough to avoid the deformation problem. These v shapes are also great to put next to the barrel tank to keep it from rolling.


I found that a pallet flipped upside down will hold a barrel from rolling nicely but I've never filled a barrel and left it on a pallet in this manner to see if it would support enough to stop the deformation.

I have one 1/2 barrel grow bed supported over one of my fish tanks using just a couple of 2 X 4s supporting either side of it, they don't come up the sides far enough to stop the deformation so I've had to add screws to the edge of the bed and tie strings accross to keep the bed from buckeling and draining over the side.


I think you will probably be better off sticking with a regular water pump. An air lift pump that can lift the water high enough to still allow your grow beds to gravity drain back to the fish tank, will likely take an air pump that will use just as much power as a tiny water pump. As I mentioned, Harbor Freight tools had little pumps that could handle a barrelponics set up for cheap. (about $16 bucks here) 20 watt pump.
Here is another place to look at pumps
http://www.aquaticeco.com/search/0/pump

They also have tech talks that discuss different things, here is a link to their air lift notes
http://www.aquaticeco.com/pages/84/Airlift-Notes
The thing they don't really talk about is that the volume of water pumped will be directly related to the volume of air the air pump provides at the pressure of the depth to which the air must be supplied. How much (CFM cubic foot per minute) air is supplied at what psi (pumping air down to a depth of 28" requires one psi of pressure.)
I'm not sure what kind of losses are involved in the efficiency of air lift pumps. Do keep in mind that many of the small air pumps for aquariums may only provide between .01 and .5 cfm. (.01 is like half a pint or air, .1 is a bit over half a gallon of air, .5 is over three gallons of air.) I am quite certain that the amount of air has to be greater than the amount of water it can lift. So a .5 CFM air pump could not possibly lift more than 3 gallons of water per minute. It is likely that it can't lift it more than a few inches above the water surface.
Here is an air pump that says it can deliver .5 of a cfm at 1 psi (if you are pumping to near the bottom of the barrel it will be less than 28" deep but you need some pressure to work.) It uses only 15 watts but it is a $$ air pump.
http://www.aquaticeco.com/subcategories/1025/Silent-Air-Pumps-by-Whitewater/v201/0
None of the cheaper pumps I see provide much more than .1 CFM though many of them are under 15 watts.

So with the current system design, how much water needs to be circulated?

Is 50 gph enough?

Or does it need to have more than that?

If I gravity drain the water back to the fish tank, at 50 gph will it provide enough oxygen in the water for the fish?

How do you determine how many gallons per hour are required to keep the system healthy? Is there a general rule of thumb to go by?

I also have a question about the barrels, If I use barrels from a carwash that were used to hold chemicals, how well do they need to be cleaned and leeched? Is there anyway to tell if they are clean enough to use for an aquaponics system?

So far I have rinsed them out, leeched them twice for 24 hours each time, and I plan on taking them to a pressure washer to wash them with high pressure water, then leech one more time. Will this be enough?

I also want to use the same barrels for a rain water collection system, will they be safe to use?

What kind of chemicals did they hold?
How are you leeching them?

The barrelponics manual is really worth the read. The barrelponics Yahoo group also has a bunch of very useful files regarding lots of things.

Why cut the beds that way? If they are cut like this :



They are self supporting and provide more support to tall plants.

General rule for water flow, is to circulate the water in the system once per hour. So 50gph would be fine. If pump is running continuously aeration would not be a problem unless there is a power out.

If concerned about fish safeness of the drums (even after washed and smell clean) fill with water and apply a sacraficial goldfish or two, leave for a week and see what happens. I uses a truckwash to clean all my barrels and tanks, even after rinsing really well (30Kl of water usage more for the quarter than usual )the water was still toxic to fish because of the soap. Took 2 weeks of pumps running, and sunlight to breakdown the soap.

FFS wheres the damn edit button

Obviously if there has been anything really nasty in the drums, do not use them no matter how much they are cleaned.

I just skimmed through it, that is pretty cool!

I think I will follow the same system design, I know there are benefits to a flood and drain system. I didnt know there was a way to do it that would not require electrical timers and things. That is really cool, I'm gonna think about how to use a system like that.

Thanks

My problem is finding food grade barrels... The cheapest ones I have found were $40!

I plan on spending $120 to build the entire system, I cant spend that much on the barrels.

Any suggestions?

Maybe I should use something else.... like plastic totes or something

They dont have to be food grade, Hydrochloric acid, free rinsing soap, truckwash, carwash etc would all be ok, just as long as its not something really bad.

My barrels had held food grade glycine without any soap in it so they were easy to wash out. Anything that has had soap in them will likely take a long time to rinse as they just keep sudsing and sudsing....... Bleach or chlorine can also be cleaned out of a barrel enough to be safe. If you know what was in the barrels and can look up the details or MSDS sheets for the product then it might be easier to decide how safe or not it is.

I got my barrels from a guy who works for a chemical company. I only buy the barrels that he can tell me what was in them. He sells them for $15 each.

I found that for a large system, the barrels just were not very cost effective since each bed requires plumbing fittings so for the large system I used wood and lined it with pond liner.

Well thats good to know, I guess I will just have to thoroughly clean them out

We get old DrPepper and Big Red 55 gallon drums here for $8 each. Pretty tasty stuff in the bottom too 55 gallon pickle barrels are also around from time to time.

Who broke the edit button

Dan,with out the edit button just go back to the way things use to be done,,,Liquid paper:)

No I tend to sniff liquid paper

Where do you find them?