My Plans

[moose]

I hope to build a smaller test system this spring. This design is to provide Talapia for weekly sales. The flow is similar to the Queensland. Tank like the one form Mexico

[GaryD]

Hi Moose,

That's an interesting approach to raising Tilapia. Is the idea of using cages in the larger tank your idea.....or did you see it elsewhere?

If it works, it would (after a few weeks) certainly provide very consistent nutrient levels for your growing system.

I'll have to wait until I'm a bit more awake to digest your system information. At the moment, if I look at columns of figures, I can actually hear myself begin to snore.

Gary

[moose]

I got the idea from Mike Sipe. http://www.cherrysnapper.com/ I talked to him this past week. Make sure you read his story http://www.cherrysnapper.com/downloads/mystory.pdf very interesting. Wtih the goal of a weekly output we talked more about the cost of running 18tanks as opposed to one tank. As I said hope to put together a smaller less intense system this spring. The O2 issue will be a major one cost wise. My reasearch seems to indicate the u-tube is the way to go due lower operational cost wise but a little expensive upfront. Need a 100 ft deep hole and O2 generator.

Sorry about all those numbers they would put me to sleep also. But then it is getting dark there now instead of the sun comming up, isnt it?

[GaryD]

Hi Moose,

My reasearch seems to indicate the u-tube is the way to go due lower operational cost wise but a little expensive upfront. Need a 100 ft deep hole and O2 generator.

How's that all work?

Gary

[moose]

As I understand a u-tube uses atmospheric pressure to saturate the water with dissolved oxygen. A tube within a tube creating a u is sunk 33' to 300' deep increasing the pressure 1 atmosphere every 33'. O2 is injected on the down pipe and water with very high ppm dissolved O2 comes up the other pipe. It does take O2 generation. But as one o the articles states due to large sizes of the pipe particulate in the water is not an issue or clogging.

http://www.pir.sa.gov.au/__data/asse...8/recirccm.pdf

http://www.aquaculturetalk.com/2009/...-other-system/

[GaryD]

Interesting stuff! Since I specialise in the design and operation of small aquaponics systems, I wonder how I might turn something like that to good effect. Drilling holes 300 feet deep is a very expensive exercise relative to the overall cost of an aquaponics system.

Any suggestions?

Gary

[moose]

It appears the even 33ft will greatly enhance dissolved oxygen. Depending on the soil that distance may be able to have a casing driven in or shot in with water. Would need a way to figure pipe sizes for return and amount of O2 generation needed. One of the big things I picked up from Mike Sipes manual is the O2 requirement matches the feed amount lb for lb. He told me that at a certain point aeration can become harmful because the nitrogen can produce a type of bends in the fish. might be easier to use the cone http://www.oxywise.com/?page=3&product=oxygen_cones in smaller systems. If you have had time to read Sipes story he seems to have the background to back up what he says. But there is usually a different and sometimes better way to get things done.

[GaryD]

Hi Moose,

The cone idea might be more practical for my situation. The slightest disturbance of the soil on my place produces the sort of rocks that landscapers would die for.

Mike does sound like an interesting bloke......and I'd certainly like to know what he does about tilapia.

But there is usually a different and sometimes better way to get things done.

Wise words Moose.

Gary

[moose]

Bset I can tell he is now in his 70s. Which does not seem as old as it used to.

[arthoz]

Rising tilapia in cages is one of the widely method used in Malaysia. We usually do it at sea, lake like the hydroponic man-made lake Kenyir and in paddy irrigation cannals. Doing it in a control aquaponics system is a good idea. I've kept a newspapers clipping on the recent effects of floods disaster here on fish raised in cage. They local officials had opened a canal gate to release water in order to lower the flood level but the toxic and low DO water caused thousands of fish raised in cages downriver to die. And those fish are not cheap tilapia but "kerapu" which is a much sought delicacy and very expensive. I can't imagine the look of chagrin on the faces of those farmers/fishermen when they've found out their whole fish stock is dying. One of them tried to pump high DO water into the cages with little success...the storms and floods season is really a sad season these past few years...I used to remember during my childhood that the "tengkujuh" season is a time of many cold restful days to enjoy warm tea and a few munchies while watching the streaming raindrops...now we are keeping watch of the unpredictable water level and news of death...