Water Recycling

[Bertie Horak]

Ok, here's my plan...
On my plot, the one boundary is a canal, from which I can fill the dam right next to it, or use the water direct from the canal.  There's a 21 meter drop from the dam down to the house and tunnel, which is about 170 meters away, but irrigation pipes already in place.  My plan - starting a fish farm, consisting of a series of reservoirs, water flowing from one to the other, down hill.  From there, the used water from the fish-breeding "dams", will flow into the last holding tank, to be used for irrigation of vegetables and herbs in the tunnel.  I'm sure the water from the "fish farm" will be enriched by the fish poop.... natural fertilizer...
Any ideas on how to better the plan?

[SandyB]

What  about a reed bed  filtration system for  all household water  ??  ...do search  and see how it   works ...

[Bertie Horak]

Thanx Sandy, will check up on that! 
I'm also looking for a kind of fish that would keep the water plants under control.  The first dam next to the canal is overgrown with water plants - all the plants you buy at the pet shops for fish tanks grow wild there, the long grassy types, as well as those with fine whorly leaves.  Somebody told me of "gras karpe" (dont know the English name) which I would like to get my hands on. Currently there's some "babers", normal "karp", as well as a few thousand goldfish - yeah, gold fish of any color thinkable! The goldfish history is another story for a later post....!

[Bob Molloy]

Hi Bertie,
                 The English name of the fish is similar to Afrikaans i.e Grass Carp. Not much good for eating though the Chinese love 'em but they are are great angling fish, they fight like hell.
In SA they're used for control but also tightly licenced as they can become a pest and destroy native fish.
They eat more in summer. An adult fish can put away its own weight in grass each day. Considering that they can grow to 18kg they are chomping through a lot of . They won't touch the feathery stuff (forgotten its name) nor water hyacinth but they certainly rip into anything else.
You can order from the wild life conservation department at De Rust or from the same department in KZN. They will only sell you sterilized fish. Pricey too, starting around R80 for the littlies. You'll also have to pay for consultation and advice on control and stocking rates so you're probably looking at an outlay of about R2,500 for around 20 fish plus all the hooha that goes with it.
If clearing is your problem they'll certainly do the job. The life span is about 9 years.
My information may be a bit dated but a call to the De Rust people will give you the good update on costs and availability.
I was last involved with this fish some years ago when part of a group looking at methods of control for a large inland lake in the far north of New Zealand. We initially steered away from carp because of its reputation as an invasive species and went down the road of mechanical harvesting. That proved so expensive and time consuming that we went back to Plan A and, after much argy-bargy with the Conservation Department, managed to source a large quantity of sterilized carp. It solved the problem within a year.
Good luck and best regards,
Bob.

[Bertie Horak]

Thanx Bob, great info!  It seems to be a bit pricey for me at this stage, but will phone anyway, who knows... After all, the dam isn't that big, probably 40m x 25m and 1.2m deep.  But there must be at least a couple of tons of yummy grass in there (if you're a grass carp, that is)!

If it's too expensive, I'll have to think about draining the dam, getting a bulldozer in to scrape it clean (apparently they do it quick-quick in one morning), and then put some kind of plastic dam lining down before filling it again - that should do the trick...

Other option - getting hands dirty and it myself... anybody have some tight-fitting wetsuits lying around?  I really dont feel like swimming with all the goggo's in the dam - I've been in the water knee-deep, and came out with a leach or two - didn't even know you get them here... and that's one critter I really dont like - I really dont feel like letting blood just for the fun!

[Michael Alexander]

Mmmh! Wonder if those carp would have been able to solve The Pink Pans Weed Problem all those years ago.....

[Bob Molloy]

Hi Mike,
             Carp will only survive in fresh water, though having said that I did hear a tale that the Pink Pan only began to grow when some bright spark decided to start pumping in fresh water from the Orange River.
Is there any basis for that story?
Regards,
Bob.

[Michael Alexander]

Hi Bob, Andrew knows more about the composition of the water, but Yes, Fresh water was pumped into the pan and with it came that that eventually choked the pan.....

By the Way, I got hold of Roger, realised I need to use large print font on the emails...great to hear that he is still around.

[Bob Molloy]

Hi Michael,
                  Great guy, Roger. An award-winning journalist and superb old school reporter who stood back for no-one. His reports during the last days of the Nat regime put him fairly in the gun and he had the usual threats from the dirty tricks brigade. I'm surprised he survived to see retirement.
Re email font size: we oldies appreciate at least 12 point black, preferably Arial. Most of us in the journo business have been staring at screens for a third of a century and often wonder why people use 8pt vanishing. Background stationery, borders and colour are a definite no-no.
Regards,
Bob.

[Andrew Darné]

Bob... about the Pink Pan. My knowledge of the fresh water story is also based on hearsay. It all happened before I came to Omund in '85. Since that time we tried draining and refilling with seepage from the sea but our efforts were in vain and had an infestation of filamentous algae which are found in fresh and salt water ponds. We tried a dose of copper sulphate which took care of the filamtous stuff for a short while but were more concerned with the enviro impact so that did not continue. The grass stayed!
The grass carp were considered but the cost would be too high for the number of fish needed and the again the "greenies" were concerned with the fish getting into the river causing problems. The only remaining solution was mechanical harvesting which also turned out to be an expensive task and labour intensive.
I came across an article published a few years ago. The waterways of Century City in Cape Town were becoming choked with aquatic and a company from oversees developed a small yet effective harvesting barge. From the photo's included it looked like a considerable solution for the earlier years' grass problem. Later other algaes became more abundant and later dominated the wtaer mass making it unusable.