surface area of hydroughton?

[Charles Gray Dorfmeier]

Hi all:

 

Im very new to aquaponics and Im attempting to calculate a vialble flood and drain system that will support 80lbs of fish using a 360 gallon tank ( about 4.5 gallons per 1 lb of fish).

 

Problem being,  I have calculated the surface area of pea gravel to use as a filter ( grow bed media) and found that I will be using a considerable amount of Gravel to filter the fish waste. Also, the amount of water that I will have to process thru the gravel beds to treat all the fish waste is considerable not to mention the resulting problem of low water levels in the tank when pumping  out to the gravel grow beds.

 

It seems that the answer to my problem is to use hydroughton instead of gravel as it will require fewer gallons of water and fewer cubic feet of grow media to process the same amount of fish wastes. Does anyone have an idea on how many pounds of fish a cubic foot of hydroughton will support? Pea gravel is about 1.4 cubic feet per lb of fish. Im guessing about half that amount of the hydroughton would be sufficient to support  one pound of fish.

 

Any info?

 

Thanks your input.

 

CD 

[Burton]

Hydroton is somewhere between 250m2/m3 and 300m2/m3
But the GB size is still very important unless you are overstocking the GB because the plants need to remove enough of the nitrates to not kill the fish.
If you go with a smaller plant base / bed then you might want to think about a mineralization tank with a specific off-gassing tank to reduce the threat of not growing enough plants to support the system.

Jobney over at aquaponicshq uses an NFT system with two filters, swirl then another you could almost call a mineralization tank followed by a MBF ... Been thinking about this design myself as a way to have two systems going at once.
http://www.aquaponicshq.com/forums/showthread.php/6569-Moving-Bed-f... 

[Jonathan Kadish NYC AA Chair]

Think of it more as a volumetric equation. The minimum volume of fish tank to filter is 1:1 so a 350 gallon tank fully stocked is going to need at least 350 gallons of grow bed with gravel or Hydroton.

[TCLynx]

surface area for nitrification is only one part of the filtration.  You also need space for mineralization of the solids and hydroton doesn't really give you any more of that than a gravel bed will and it is the solids and plants that really require more space than the actual nitrification part of the filter.

Here is a page with some blog posts about my 300 gallon system where I have a 300 gallon fish tank and 6 100 gallon grow beds.

[Charles Gray Dorfmeier]

I have read that red worms  placed in grow beds will aid  in the mineralization process thus off setting the need for a mineralization tank,  is this correct?

 

 Burton said:

Hydroton is somewhere between 250m2/m3 and 300m2/m3
But the GB size is still very important unless you are overstocking the GB because the plants need to remove enough of the nitrates to not kill the fish.
If you go with a smaller plant base / bed then you might want to think about a mineralization tank with a specific off-gassing tank to reduce the threat of not growing enough plants to support the system.

Jobney over at aquaponicshq uses an NFT system with two filters, swirl then another you could almost call a mineralization tank followed by a MBF ... Been thinking about this design myself as a way to have two systems going at once.
http://www.aquaponicshq.com/forums/showthread.php/6569-Moving-Bed-f... 

[Charles Gray Dorfmeier]

For some strange  reason  I  couldnt  access the page  with  the  blog  posts. Can  you provide  the  actual  web  address?
 
TCLynx said:

surface area for nitrification is only one part of the filtration.  You also need space for mineralization of the solids and hydroton doesn't really give you any more of that than a gravel bed will and it is the solids and plants that really require more space than the actual nitrification part of the filter.

Here is a page with some blog posts about my 300 gallon system where I have a 300 gallon fish tank and 6 100 gallon grow beds.

[TCLynx]

http://www.aquaponiclynx.com/category/systems/300-gallon-system

or just go to my web site

http://www.aquaponiclynx.com/

and half way down the right hand side bar is a box where you can look up blog categories and choose 300 gallon system

[Charles Gray Dorfmeier]

ok  thanks for the help!

 
TCLynx said:

http://www.aquaponiclynx.com/category/systems/300-gallon-system

or just go to my web site

http://www.aquaponiclynx.com/

and half way down the right hand side bar is a box where you can look up blog categories and choose 300 gallon system