Backyard Aquaponics
A place to discuss aquaponics

Hi I'm new here, posted a bit about myself here this morning :

http://www.backyardaquaponics.com/forum/viewtopic.php?t=236&start=114

I'm keen to hear what you all think about the sustainability of keeping my yabbie population up to a moderate (say 50 or so) golden perch ?

I intend to feed the yabbies if required (loosen hay and other tidbits) which will inturn be feed for the golden perch (or other species).

There are a large number of tall reeds in areas of our dam, hence places to hide for the fish and yabbies.

I guess this is not the typical form of aquaponics discussed here but ...


What other options do I have with a dam ? I could load up the dam with fish and run plenty of plants either on the dam surface or in external filtering/growing areas for a complete cct ?

Strud

limiting factors with dams are usually feed rate and airation i think..........not nitrate build up i think..............

Steve,

I do have a very grunty pump at the dam (2.4kW motor with multistage grundfoss pump that supplies most of our properties paddocks) that I could use to recirculate and aerate with a venturi air mixing jet.

It is a large surface area (about 50m by 20m), not sure if that is a problem.

Strud

hi Strud and welcome,

I have no experience in this matter but stay with us and advice will start trickling in from more knowledgable ppl

what inwas getting at strud, is that that you could stock HEAPS of fish if you provide feed and air without ever having to worry about plants or nitrate removal, or even having levels needed for good plant growth.........know what i mean?

Others please chime in!

John from Jamberoo Aquaculture would be the one to answer most of your queries Strud....

As I understand it, it's not just enough to oxygenate the water.... what you see most of the big paddle wheels doing.... but in larger ponds/dams the problem arises through a seperation layer effect with the lower colder layer becoming oxygen deficient and ultimately anerobic....

Sure John could explain better, maybe PM him Strud....

http://backyardaquaponics.com/forum/pro ... file&u=805

I know John has effectively modified his operation to enclose his fish stocks into cages within the dams, through which he bubbles large quantities of air from deep below the cages.....

I believe most State fisheries are now recommending conversion of dam type operations to cage technologies, partly to prevent non-native species escapes during flood periods.... certainly it is becoming almost impossible to obtain licensing to stock natural or manmade dams/ponds within natural waterways/runoffs like the days of old....

Everything now must be purpose built within strict guidelines.... or NO license(s)..... at least here in NSW..... and many of the older operations are being phased out and certainly not relicensed by Fisheries when ever the occassion might arise.

not to digress too far i think strud was looking at incorporating AP into his 1.5MEG dam.

my question is would you need a ridiculous amount of fish to make it happen and is he looking for that many fish that his dam would require airation..........

I think the best way to aerate a dam would be to have a big header tank, a solar panel, a pump and a [s]paperclip[/s].

Pump the water to the big tank during the day and at night empty it back in again and make as much water turbulence as possible.

That and the use of flood and drain there should be adequate splashing.

i hate to be a pain but i think you meant lucerne not loosen

Ding dong

Delgrade,

You're very correct, a bad habit I have of spelling that word that way ..

Are others feeding yabbies and related species lucerne ? What other feeds are they typically given ?

my pop feeds his yabbies crushed lupins, but i couldnt tell you how much or how offten, i do know that the need to be crushed