Pilot Commercial NFT System

tonyabalone

Since February of this year Challenger Institute of Technology (Fremantle, Western Australia), in conjunction with the Armadale Noongar Corporation ( ANC), have developed a pilot commercial aquaponics system. The system is now finished and so far the system has performed very well. The first lettuce crop will be harvested next week.

The system consists of a 5000 litre tank, a modified Vortex filter system, 1000 litre sump tank with a submersible pump and 16 x 6 metre NFT channels. An inexpensive shade cloth system has been built to protect the plants from winds, frost, crows and a uniquely Australian problem of Kangaroos. Two systems have been installed with the ANC and trialled. At the moment each tank has approximately 350 Rainbow Trout. This will give a carrying capacity of about 35 kilograms per cubic metre. I’m confident that further trials will show that the system can handle higher carrying capacities
The key to the system working efficiently is getting the wastes out and maintaining the oxygen levels. The wastes are removed by an effluent arm that results in the tanks being self cleaning. All the solid wastes are sucked up by the effluent arm and taken out by a swirl separator. High oxygen levels are maintained ( 98 % saturated) by splashing the water as much as possible as well as a series of air stones strategically placed. One air blower is used to service both tanks.
The system has attracted a great deal of interest from those who have seen it and another company is expected to install a system in the near future.

creative1

Tony - Are you concerned at all about removing ALL of the solids
and having to suppliment the nitrate( & minerals etc) demand of the NFTs?
I only ask because with my system I extract NO solids( cept the GBs) and the system runs at 0, 0. 0.
I have good plant growth but some people have issues with plants yellowing and performing poorly
when the fish load is low.( as I would expect removing ALL the solids would effect similarly)

Though if you only grow light feeders then this might not be a problem?
C1

earthbound

Sounds interesting Tony, can you tell us a little more about the effluent arm? Or do you have a picture of it?

Gavin gave us a couple of pics of this before I'll try and find them and link them in here so everything is in the one place.

Aquastud

What PH do you run? I was up at Port Stephens NSW and visited Tailor Made Fish Farms who grow Barramundi and Lettuces. They produce about 1000kg of Barramundi a week, which are sold live and end up in the Sydney Asian restaurant trade, and they produce about 2000 Lettuces a week. They use some of the waste water from the fish system(10% water change daily) and put it through an NFT system with extra chemicals added. I asked why they didn,t use an AP style system and they said because you can't get the best out of both, to run the fish farm hard you need the PH in the high sevens and for the lettuces in the low sixes.
An interesting part of the fish farm was the effort that was put in to grading, the young fish are graded weekly for the first 4 months, apparently Barramundi are extremely cannabalistic when young, they had a bottle full of dead fishes with other fishes almost their size stuck in their mouths. After the grading period they go into the final grow out tanks for 5 months where they reach 750g harvest size. http://www.tailormadefishfarms.com.au/

earthbound

I don't know that Tailor made are still running the AP are they? Last I heard they were just pushing the aquaculture side of things.

TCLynx

I expect there is more leeway on the pH than most "experts" insist. As Joel often mentions, many of his systems run fine with rather low pH while I am managing to grow quite a lot of plants with a rather high pH.

Problem is, most commercial ventures don't have the luxury of taking things slow and experimenting till they find what does work for the situation since they have to turn a certain amount of profit or go bust.

The comments about the solids removal and the other notes about the system doing more aquaculture and using the exchange water for the plants makes me wonder. Perhaps an aquaculture system could have it's solids removed to a mineralization tank hooked to the plant portion and use exchange water to actually get the benefit of the mineralized solids as well as the nutrient rich water while being separated enough to allow pH adjustment for the plants. Would require more monitoring and labor than a standard backyard system of course but that is the nature of commercial ventures.

tonyabalone

Hi Joel,

i should correct an error. The filter system uses an off the shelf Oasis Vortec 20000 pond filter. If you Google the name you will get more details of the three chamber product. I modify ours so that the very clean surface water is taken by two 50 mm pipes into the second chamber. The solids are taken out by the effluent arm which has an outlet 150 mm below the surface. Thus water pressure ensures that the effluent arm is always sucking wastes from thre bottom. have a look at the previous photos anf the ones I'm about to ad. The water is introduced back to the tank in such a way that a swirl pool action occors taken all wastes to the centre bottom of the tank.

gemmell

Water looks incredibly clear - especially given that the tube is clear and looks like it's got some sun! I'm surprised there's no algae buildup on the walls - whats the secret there? (I'm guessing the water's running too fast for it to settle on the sides or that it's some special type of tube). Or is that an old photo?

Nocky

Looks very elaborate tony, isn't it slightly over engineered, and 350+ trout sounds like a lot in a 5000lt tank, isn't it better to have room to grow? obviously removing the solids hasn't affected growth, sort of changes a few AP theories I guess, but it looks high maintenance :dontknow:

RupertofOZ

Nocky wrote:

sort of changes a few AP theories I guess, but it looks high maintenance :dontknow:

Not really Nocky.... the UVI model removes solids... and just uses the nitrate rich water to supply the rafts...

An NFT model isn't that different.... and if you have a look through my "mega" system thread you'll see I've been running a 20 channel NFT unit very succesfully... for several years....

It's "AP" in the sense that it utilises nutrient rich water from fish... but nothing new... Taylor Made and Barramundi Blue have been doing it for years...

The basic media "flood & drain" theories still hold true...

The above mentioned "commercial" operations are more aquaculture with an add-on "effluent" treatment/reuse of water that would otherwise be problematic to dispose of...

And both the above are still "run to waste" systems... that either only partially use the water.... use for one pass and dump.... and/or regularly water change...

A few questions to you Tony, along the lines of the above, and TCL's comments....

Just what do you do with the removed solids... do you do regular water changes, if so based on what variables... and are you in fact supplementing the nutrient supply to the NFT with anything??

tonyabalone

I’ll try to answer the series of questions that I’m getting in one post.
Firstly creative 1 the solids are taken out of the fish tank almost immediately to avoid anaerobic condition developing on the tank bottom. For an NFT system to work the water must be very clean before it is introduced into the NFT channels. With such a high stocking density the amount of feed is high so there is a high effluent load. The swirl separator is cleaned out every second or third day.
As for plants yellowing we spray the leaves of the plants approximately three times a week with Thrive. This ensures that they get the trace elements that are lacking in fish waste. It is only a light spray on the leaves and we take care not to have the solution dripping into the water. Thrive has certain chemicals that fish don’t like such as copper.
Aquastud we try to maintain the pH around 7.0. With the high biological activity in the biofiolters however the carbonates are being used up so we supplement with calcium carbonate. I was very interested in your information about Tailormade. Thank you.
TCLynx our comments about commercial systems using mineralzation processes to break down the fine solids is already happening with the UVI raft system. And your right our NFT system does require more labour and daily input than a small home system..but then that’s what you expect in a higher production commercial system.
Gemmell, your right the photo of the filter system over the sump tank was taken early in the building process when there were no fish in the system. You can see that by the fact that the shade house still had not been built. All the fish tanks are covered with shade cloth and hopefully you will see this when I post another photo below.
Nocky your comment about over engineered is a matter of opinion. I understand your point but what matters is whether it works or not. Yes as I said earlier the higher production levels do put more strains on the system and yes there certainly is more maintenance is involved.
As I said earlier this is a trial of a pilot commercial system and time will tell how it performs overall.
I’m happy to keep you updated.

earthbound

Yeah, careful with the thrive Tony, Murray managed to kill all of his fish at one stage by using thrive. :think:

RupertofOZ

tonyabalone wrote:

As for plants yellowing we spray the leaves of the plants approximately three times a week with Thrive. This ensures that they get the trace elements that are lacking in fish waste. It is only a light spray on the leaves and we take care not to have the solution dripping into the water. Thrive has certain chemicals that fish don’t like such as copper.

Yep... a few fish kills by several members many years ago at the start of their aquaponics adventures.. taught us all to avoid "Thrive"...

Knowing the potential impact of "Thrive"... and particularly the copper content... why didn't you go with Seasol/Maxicrop... or a similar seaweed extract instead Tony... as has been constantly mentioned/recommended here on the forum for many years.... :dontknow:

RupertofOZ

tonyabalone wrote:

... we try to maintain the pH around 7.0. With the high biological activity in the biofiolters however the carbonates are being used up so we supplement with calcium carbonate.

See Nocky.... the same AP theories... remain the same ... :wink:

RupertofOZ

Tony, is that Oasis Vortec 20000 servicing both 5000L tanks... what sort of flow rate are you running through it??

Backyard Aquaponics
A place to discuss aquaponics