permaculture

[<permed@nor.com.au>]

>G,Day Robin; everybody:)
>In a message dated 8/13/02 7:11:34 PM, permed@nor.com.au writes:
>
><<  A healthy pond will support a nice stock of fish for home 
>consumption with no extra input at the natural stocking rate of the water 
>body - rule of thumb is 1 kg of fish for every 15m of linear edge (drives 
>the food chain) and 15 square m of surface area (oxygen for fish to 
>breath). >>
>
>Hmmm...my concern is that the pond may not be healthy. The water is quite 
>turbid, fills only with surface water, is fairly stagnant, and used by 
>cattle. Seem to a good number of frogs, and a blue heron can normally be 
>seen 
>at certain times...normally when cattle etc. are elsewhere:)

My ponds are only surface run-off, stagnant, low turbidity and productive 
- main difference with yours is cattle. with cattle excluded, appropriate 
water plants and edge vegetation you should see water quality improve.  
Frogs are a good indicator - they're very sensitive critters to 
environmental pollution. 

>The pond is a half acre + with 600'or so of linear edge. IF the pond were 
>healthy how many fish would that support? 
600'= approx 200m thus approx 13 kg of fish  or around 25-30 x 1lb fish
half acre = 2000m2 so oxygen exchange could potentially support 10 times 
the fish stock

My main dam is nearly 1 acre surface area, stocked with 50 fish and no 
extra feed or aeration.
Hope this has helped
Robyn