Backyard Aquaponics
A place to discuss aquaponics

A short story in the IHT/NYTimes about a saltwater hatchery/small fish farm located on terra firma. They use hydro-cavitation to oxygenate the water to purify it. Of course, pressure changes and oxygen bubbles only kill small lifeforms. Doesn't do a darn thing about the nitrogen in any of its forms. So that means they have saltwater tanks and need to do water exchanges or have a traditional bio-filter and do fewer water changes. But they'll still need a lot of water and the waste water will be saltwater. In Singapore it is a short run of pipe to the ocean, but the article suggests they want to move it inland. From what I've read, the inland brackish water Thai shrimp farms are causing havoc with the water table. Can't imagine what large scale saltwater farming inland would do. Am I missing the environmentally friendly part? Or is there a way to do straight aquaculture without water changes - that's not called aquaponics.

http://www.nytimes.com/2010/10/28/business/energy-environment/28iht-rbobsingfish.html?_r=1

I once saw someone doing "aquaponics" where they were trialling growing salt water fish and the green "seaweed" that's often on the rocks around the coast (cabbage, green weed etc).

That was pretty cool.

A number of places do do water changes but put the water into remediation ponds where the same basic processes as what you get in an aquaponics GB, take place. They then use the water again.

Aquaponics is just a word for a certain type of aquaculture that comes under the label of Integrated Aquaculture - there are a lot of variations out there.

Google "Integrated Multi Trophic Aquaculture" and you see some good examples.

The company in the article didn't strike me as the seaweed growing/remediation pond kind of people. More of the, hey we can kill the algae without chemicals and do it cheaper so lets see if we can get some green press, kind of people. Though the cavitation is a neat idea for algae/disease issues.

With saltwater remediation ponds inland from the sea you still have to fight evaporation raising your concentration and torrential rains diluting it/washing it into the ditch problem. And it still doesn't address profitably building a pond that won't leach saltwater into the fresh groundwater.