2000 gallon tank and 256 square feet growbed

[scotteboy]

Hi everyone. I am new to the forum. I`ve been researching Aquaponics for a while now an am ready to start a full on system.

The aquaponic community in Canada is still small, as far as I have seen. And only a few colleges and universities have anything related to this subject.

Looking around town I have priced out some equipment.

2000gallon water grade tank = $1500
8'x4'x12" Flood Table = $140
1200gallon per hour Magdrive Pump = $200
OR Sump Pump $200-250
Air Pump = Have
Food Grade Barrel = $35

With the stands and piping I figure it to cost around $4000 Canadian.

Basically the system will consist of 8 flood tables totaling 256 square feet, each bed equipped with a bell siphon and filled with 3/4" washed river gravel. The fish will be in the 2000 gallon tank and the sump will be in the 50 gallon barrel.

A few questions I have are:
How long should it take to fully circulate the 2000 gallons?
How much produce do you typically get per square foot of aquaponic grow-bed versus soil?

Please post any links to a thread with a similar sized system.

Thanks all!

[keith_r]

a "basic" rule of thumb is that you want to pump the volume of your fishtank through the growbeds 1x per hour..

you've got about 1400 gallons of growbed, personally i'd base my fishload on the growbed volume, 25lbs/100 gallons max and that's the grown out size of the fish.. a good starting point is 1gal gb to 1 gal ft, better is 2gal gb to 1 gal ft

you'll need at least a 700 gallon sump to fill the growbeds and leave enough water so that you aren't sucking air, unless you use a spider valve with a timer or some very interesting flow controls..
good luck read lots
we like pic's

[cedarswamp]

"you've got about 1400 gallons of growbed"


I come up with 1915 gallon of GB. :?:

[rfeiller]

welcome to the forum

[keith_r]

it was late.. yeah,, pretty close to one to one there..
i'd still go for a bigger pump

[scotteboy]

Thanks for the feedback. I wil look into a bigger pump. So I'll recap and ask a few more :)

-Bigger Pump, cycle water once an hour.

-Better to have 2:1 growbed:fish tank ratio.

-25 lb max of fish to every 100 gallons of water.

Will it work to have the beds FILL by gravity, drain with siphons into a sump tank and then PUMP the water back to the fish? If anyone has done this, please post a link.

I was looking at doing FLOOD-DRAIN. Is it More effective to do CONSTANT DRIP and let gravity drain the beds?

For pumps, what works better: a constant flow pump like a magdrive/pond pump OR have a house style sump that automatically turns on and off in a sump tank?

Thank you in advance!

PS. This is for a community garden display/ informational setup.

[keith_r]

actually, it's 25lbs max fish for every 100 gallons of growbed..(that's your filtration)
i've seen a few different systems and system tests.. flood and drain, constant flood, timed flood and drain..
if you do go 2:1 growbeds to fishtank, you pretty much have to have a sump, here's what i've seen and am going to try to do;
fishtank with (2) overflows that go into growbeds, growbeds drain into sump, sump has a pump that pumps into fishtank-they call this CHIFT PIST or constant height in fishtank, pump in sump..
trials i've seen show that constant flood does pretty well, and may be the most "forgiving" - more water volume/more stable temps, but i have not done this type of system... yet i may end up with a mix of flood and drain/constant flood
oversize your pump, the "head" is the distance from the surface of the water to the highest point you are pumping.. if you oversize the pump, you can divert flow back into the fishtank to provide additional aeration
good luck, take lots of pics, and keep asking questions

[scotteboy]

Would a aquaponic system require a special pump or would something like this work http://www.homedepot.ca/product/sewge-p ... nal/928228 (http://www.homedepot.ca/product/sewge-pump-3-4-horsepower-cast-iron-professional/928228)

[cedarswamp]

Would a aquaponic system require a special pump or would something like this work http://www.homedepot.ca/product/sewge-p ... nal/928228 (http://www.homedepot.ca/product/sewge-pump-3-4-horsepower-cast-iron-professional/928228)

Way overkill IMHO, thats a grinder pump. 2" solids? That's a big fish. :lol:

[rfeiller]

you might want to start out with a 1 to 1 ratio and as the system settles in the nitrates will reach a point where it can handle the second GB then add it. you may want to stagger your crops anyway so that you don't end up with everything rippening at the same time.

[davidstcldfl]

Hi scotteboy, welcome to the forum... :D

[urbanfarmer]

Greetings Earthling, and welcome! :mrgreen:

[urbanfarmer]

1915.01 gallons maximum on the grow beds filled at perfect level to the top with no gravel. 1755 gallons if filled 1" below the top with no gravel. Assuming the gravel takes 60% of the volume that leaves 702 gallons of grow bed that will fill with water. You will likely need 3x the grow bed space to maintain a ratio of roughly 1:1 in your system. pH will play an enormous factor in the required ratio for you system; so, don't push the minimum limits too hard because a pH fluctuation can kill your fish in a short amount of time. The same goes for temperature.

I couldn't see the pump (website down), but I prefer pumps that pass larger solids for gravel grow beds. The efficacy of bacteria to decompose waste matter is positively correlated to the surface area to volume ratio of the matter. If you have worms in your grow beds, that's not as important. But, check the wattage on the pump and make sure it you get the extended warranty. Make sure the pump is okay for continuous usage.

How long should it take to fully circulate the 2000 gallons?
It depends what you are asking. To determine how many gallons circulates in an hour, you just look at the GPH (gallons per hour) of your pump. If you mean how long does it take for the concentration levels to decrease to 0 based on 100% biofiltration efficiency and assuming no increase in the fish waste, the mathematical answer is infinity. Although, from a practical standpoint it would only take a few hours based on a GPH equal to the size of your system's water volume to get the levels to acceptable numbers or even undetectable levels. It's an exponential function of decreasing magnitude.

How much produce do you typically get per square foot of aquaponic grow-bed versus soil?
Depends. You could get worse than soil if you have no idea what you are doing! :lol:

Numbers have ranged from 100% of the production, comparatively, for the same plants on the same surface area in soil to numbers higher than 30,000%. Yes, that's the right number.

So many factors will affect this. Aside from the usual, sun, nutrients, temperature, cultivar, species, etc... you also have how well you design the use of your square footage. It is really quite variable, but in general you can assume a greater production per unit surface area. Vining fruiting plants typically have the greatest increase in efficacy from a comparative standpoint. That's obviously because they make use of their vertical space. We live in 3 dimensions after all, and it's misleading to compare based on surface area instead of volume used! :ugeek:

[scotteboy]

I bought a pump today for a smaller system (to get a demo going). Ive decided that it will be similar to Murray H's design down in Auz. The pump is a eco396 submersible, continuous flow. $35 at Progressive Growth Hydroponics.

Stock tanks at the local farm supply store appear to be the best bang for buck... deep tanks, sturdy (not rigid). For the fish Ill use a oval 110 gallon (not filled completely) $83 and for the growbeds I'll pick up 2 x 75 gallon $80each (3'x4'x18" approx). Most likely on Tuesday (whoo hoo EI).

Have to whip up a frame to hold the beds, will post pictures when in progress.

Cheers!

[scotteboy]

Is there anyone on Vancouver Island (british columbia, canada) that has a working aquaponic setup?

Where in Canada can one purchase fiberglass growbeds or fish tanks?

[urbanfarmer]

I look forward to the pictures! :-D

[scotteboy]

Started the plubing today. Found a 9' fenced yard outside a local hydroponics shop to showcase the system. Super high visibility, power, equipment..... seeeeeet.

I'm using PVC and marine goo to gue the parts, im assuming its safe for food and fish... we'll see :D