Aquaponics "Mythconceptions"

[Pugo]

Well, my growbeds are 150mm gravel and I seem to be able to grow anything I want. I don't understand why everyone thinks this 300mm is some kind of a magic number, Look at NTF systems the water is only a fine film media depth is nothing, If you are running a basic flood and drain system with no filtration and a low density of fish, then 300mm growbed being used as a bio-filter may have a purpose. However other than that I see no reason to use that much media in a growbed.

[Damon]

i think what hurts aquaponics the most is people's limited knowledge of perspective... i've learned that keeping mosquito fish is illegal in some part of the world, so having raft systems would be a bear to deal will... that being said, sometimes things aren't the same for all systems...

now, although solids removal is a big topic, most people only have 2 concepts to choose from in the main stream... you wither have a mechanical filter, or worm bed. but what i've seen is the use of gammarus is more efficient that both of them combined, and produce the effect of both of them combined.... the gammarus are so efficient at eating the waste solids and mineralizing them that once a population of them begins to grow, using mechanical filters will be a thing of the past and be labeled redundant... they also achieve what the worm beds seek to provide, which is the mineralization of waste solids.

my point is if people dont have something in their system, or they have it and they're not paying attention to it, then they arent going to talk about it.

since i've been hearing more and more about the vermiponics i've been wondering if gammarus have actually shown up there also to relieve some of the burden of the solid wastes? or if people are only paying attention to what they put into their system and not to what mother nature puts in their system when they aren't looking.

[GaryD]

Hi Damon,

now, although solids removal is a big topic, most people only have 2 concepts to choose from in the main stream... you wither have a mechanical filter, or worm bed. but what i've seen is the use of gammarus is more efficient that both of them combined, and produce the effect of both of them combined.... the gammarus are so efficient at eating the waste solids and mineralizing them that once a population of them begins to grow, using mechanical filters will be a thing of the past and be labeled redundant.

With respect, I think you need to spend more time in a recirculating aquaculture system before you can make a prediction of that type.

In a RAS, the goal is not mineralisation......it's nitrification.

Mineralisation is the biological conversion of organics into its fundamental chemical compounds. Aquaculturists are not interested in the mineral make up of the water in which their fish live (in terms of how useful it is to plants).....but rather converting the toxic substances generated by the fish into less harmful substances (nitrification).......in the interests of conserving water.

As things currently stand, RAS operators use a variety of mechanical devices to remove as much of the fish waste as they can and to convert what's left into something that their fish can live with.......with pretty predictable effect.

While I'm interested in Gammarus from an integration perspective, most fish farmers wouldn't have the time or the inclination to bother.......and nor would they likely bother with the infrastructure that it would take for the scuds to colonise the system in sufficient numbers to replace the mechanical and biological filtration that they currently use.

Damon, these are folks that sleep (not always well) with system failure alarms alongside their beds. When something goes wrong with their systems, they often have minutes (rather than weeks) to deal with the situation.

Gary

[GaryD]

Hi Pugo,

If you are running a basic flood and drain system with no filtration and a low density of fish, then 300mm growbed being used as a bio-filter may have a purpose. However other than that I see no reason to use that much media in a growbed.

Even then, most researchers are in agreement that grow bed area is more important than grow bed depth.

Grow depths of 300mm, as a required/preferred thing, arose from unsuccessful attempts by advocates of the basic flood and drain system to extrapolate the Speraneo model into universal usage.

Gary

[kellenw]

Damon, these are folks that sleep (not always well) with system failure alarms alongside their beds. When something goes wrong with their systems, they often have minutes (rather than weeks) to deal with the situation.

Gary

So true. My monitor and control system calls, texts and emails me and two other people if anything is the slightest bit off. It also sounds an audible alarm in the facility itself. This is standard practice. It has saved more fish than I can count, because things do happen, and need fast correction. I hate getting out of bed at 3 o'clock in the morning because of an alarm code, but I always thank my lucky stars I did! hehe

I wouldn't, in good conscience, allow any owner/operator I've done work for, operate without such a system either.

[Damon]

gary, i now the difference between the two, the point i was making was the that the gammarus keep the AP systems clean enough to not have to deal with cleaning filters. their main population points are in the solid settling tanks, and in the gunk that falls from the net pots and collects in the bottoms of the troughs.

now would i use them in a purle aquaculture set up? probably not. the amounts of fish waste would be ridiculous... you'd need a large marsh type bio-filter like the wetlands of florida to give the scuds enough surface area to live and breed and also have enough space for the water to flow and allow the solids to settle to the bottom... although it is a big project, it's still fathomable...

[Earthan Group]

So true. My monitor and control system calls, texts and emails me and two other people if anything is the slightest bit off.

lol a recent build we did had delays with the electrician connecting the alarms. The monitoring gear was in but we were waiting for it to be connected. So I had the pleasure (for want of a better word) of getting up every 2 hours checking the system and the stock through the night in rotation with the new owners lol. When you have $80,000 of stock (worth $500,000 on the local market and 4 million on export) in the system you kind of what to be sure your money is ok.... In a new system later this year we can monitor and adjust everything (valves, pumps, dosers etc) on the iphone.... much more fun.