Backyard Aquaponics
A place to discuss aquaponics

I have been an avid aquarist for over thirty years. I have owned a couple pet/fish stores and a large aquarium maintenance business here in Colorado. So I have a lot of knowledge about fish and their requirements. Also about getting optimal growth and health from those fish, I just sent this link to a friend and thought some of you may be interested.

http://www.wetwebmedia.com/FWSubWebInde ... tChems.htm

So doing a regular water change will help keep these Growth Inhibiting Substance(s) at low levels or even out of the water. In a balanced system, this will not affect your nutrient level (depending on the water change water) and NO topping off the system for evaporation DOES NOT count as a water change. You must physically remove tank water and replace it with new water.

Scott

I would suggest that his research and findings are based on aquaria, which is similar - yet different - to AP.

I believe that the 'ponic' component of AP, as opposed to straight aquaria, would mitigate a lot of these listed issues through it's biological and biochemical processes.

But it would be interesting to hear the verses of the more sagely members and/or seeing similar tests done in AP that aren't based on aquaria or recirculating aquaculture.

BTx

The research is most definitely based on aquarium fish, and in reality, to me any way, aquaponics is really no different. You are balancing your fish stock (nutrients) VS the ability of the system to absorbed those nutrients (plant material). All of this whilst maintaining a chemical and pH balance in the system for the overall health of the system and anything reliant on it for life. In the larger water volume present in the AP system VS the typical home aquaria yes there is substantially more water which will dilute any hormones that may be present yet the denser population of large fish will undoubtedly produce a larger quantity of hormone per unit of water volume.

An interesting debate and a queeriosity for sure.

Scott

Which is probably exactly what is occuring in a closed loop aquaponics system anyway....

And is exactly what is happening in a "natural" system.... where freshwater fish are growing....

Exotic,ornamental aquaria fish... in small volume, sterile, un-natural aquatic environments... often treated with a miriad of different chemicals... ultimately bounce up and down like a frenetic pogo stick...

And the ultimate solution... is throw out all the water... and start again... until next time....

Most aquaria practices, and chemical solutions... don't translate to aquaponics... and/or edible fish for human consumption...

Even in aquaculture, which has been thouroughly researched for decades... water changes are only done as a last resort ... primarily to discharge high levels of ammonia, or nutrients...


IMO... aquaponic systems mimic natural, balanced systems.. with all the beneficial hetrotrophic bacterial consequences.... and generally don't require water changes at all...

It would be interesting to actually read some of the literaature behind the claims...

As often fish excrete "debilitating" chemicals ... at times of threat, attack or stress...

We try to avoid such circumstancves... as inevitably that leads to pathogen attack....