Backyard Aquaponics
A place to discuss aquaponics

Definately possible to put a bog type section into a system... And I would imagine that for ultimate removal of wastes your probably right about have aerobic and anerobic, though bogs do have amazing abilities to remove allsorts of wastes..

I have often pondered a small spa/plunge pool type thing that is filtered by using a number of small growbeds filled with bog type plants, rushes, reeds etc, do away with the chemical side of things.. I know they can do it with natural pools, so I would imagine that it wouldn't be too hard to rig up a system for a small spa... Wouldn't be able to heat it to much though....

Yes EB, Steve, I have read that link too..book marked it for reading again.... very good.......It is just amazing what nature can take care of for us if we just give it the right conditions and don't interfere too much in the natural order of things.
That is what is so amazing about this Aquaponics thing ...a good example of what natural processes can do.
Modern man has become so smart in manipulating the environment, food etc that we have become dumb to the simple and what should be obvious.....we need to re learn the simple things....
Wow, heavy thoughts there for breakfast !!!
Murray

I'm afraid to look into things like that - I know I will want to include something like that into my system... which is difficult as I dont realy have a 'system' running as of yet - I only have the ponds running, 2 yabby and about 8 feeder fish in the ponds - but no grow beds as of yet - still waiting on the grants (who knows, I might still get one as we are waiting to hear about 2 we have submitted)... but I agree, nature has a wonderful way of dealing with things in a very simple way.

Mini-wetlands (or bogs) are effective means of removing all manner of pollutants from water.

Our interest in mini-wetlands arises from our desire to clean and polish domestic greywater but the biology is just as relevant for Aquaponics.

If you'd like to learn more about mini-wetlands, see http://www.hydroponics.net.au/back_issues/issue62.html

Mini-wetlands can be scaled down to suit quite small volumes of water and they are inexpensive to construct. They often comprise 4 modules:
1. Sediment trap….removes sediments, lime enriched sand absorbs phosphates…..this can be covered to avoid odours and insects. The phosphate-laden sand is replaced periodically with fresh sand and lime.
2. Soil and Grass Filter Bed……grass absorbs nitrogen and can be harvested. The nitrogen (which is bound up in the grass or other plants) is removed from the cycle when the plants are harvested.
3. Wetlands……reeds and other plants capable of removing nutrients.
4. Retention Pond…..which can be used to grow duckweed (or Azolla).

Aquaponic grow beds work like the grass filter beds (and could substitute for them). They also perform like #3......like a biological filter.

We have set of flowforms which will also become part of our greywater treatment system.

Here's how they work. As water passes through the flow forms, it takes up a pulsing figure 8 movement -very much like the swirling motion of a mountain stream. This action oxygenates and re-vitalises the water.

Polluted water (like that in fish tanks) contains high levels of nutrient which consume oxygen. When the oxygen levels in the water drop below a certain point, and nutrients (like ammonia) increase to a certain point, dead fish aren't far away.

We planned to use our flow forms as part of our greywater treatment process. They provide the dissolved oxygen required by the micro-organisms which break down the nutrients in the water. We intend to use mini-wetlands to remove the fats and most of the phosphorus and nitrogen. The flow forms were then to be used to ‘polish’ and re-vitalise the water to further improve its quality.

Given our interest in aquaponics, they could just as easily end up as part of our aquaponics system. With a little design work, they may serve both.

If you want more information on flowforms.....just ask.

Gary

Im going to be using polystyrene boxes for my trial system (to grow ornamentals and ferns to start with)... what's the [glow=red]bad[/glow] news on polystyrene?? [schild=18 fontcolor=000000 shadowcolor=C0C0C0 shieldshadow=0]poisioning me?[/schild]

Hi Gary - that link doesn't seem to be to an active page.

It would be great to hear some more about flow forms. I don't know anything about them. What have you made them from? Can you provide a picture or diagram to help me understand?

At my place I have a septic and grey water, so I would be very interested in the design not only to do with my aquaponics interests, but also for treeatment of my grey water.

Thanks.

Hi VB,

Try going into http://www.hydroponics.net.au then click on Free Articles and scroll down to Issue #62 and you'll find the article on mini-wetlands.

For a couple of photos of our flow forms, got to www.duckweed.info and look in our photo gallery. For more information on flowforms......try http://www.flow-forms.com/.......or http://www.nationalwatercenter.org/flowforms.htm ......or http://www.waterflow.net/

Ours are made from concrete and cost about $1250 for the whole set up including the flowforms, hardwood stand, pump and fittings. They are also available in fibreglass.

Our flowforms could probably only be justified for inclusion into a fairly large aquaponics system (perhaps 10,000 litres or more) but they are available in many shapes and sizes. We set ours up over a 250 litre tub just so we could watch them work. The sight and sound emanating from a flow form is as good for the soul as it is for the water.

Mini-wetlands would be my preferred approach for treating greywater -largely because they can be constructed at minimal cost. The microbiology associated with wastewater treatment is the same as for aquaponics. Nutrient-laden water from the fish tank is virtually wastewater (without the detergents) until it has gone through the grow beds.

The treatment for both greywater and nutrient-laden fish tank water is very similar. Grow beds are biological filters. The only difference between grow beds and the trickling bio-filters that can be found in any sewage treatment plant is the size and the fact that grow beds have plants in them (as well as the bacteria).

Mini-wetlands are similar again but have lime-enriched sand beds (to trap phosphates) and grass beds (to remove nitrogen) and reeds and other plants (which are able to take up all manner of other things including heavy metals).

Gary

Gary

WOuld just need to watch the final resing place for those reeds gary? I mean whats the point if you remove heavy metal from the water to then eat it or use it as compost for the garden?

The same might be said for detergents or other synthetic compunds contained in domestic grey water. I'd be worried about using plants grown in this water as food. Maybe as compost as per the other post on compost detoxifing compunds via slow microbial action.

Comments Gary?

Great info thanks Gary....

VB, AM,

for the past TWO HOURS i have been doing research on the net.
My eyes hurt, my contacts are about to drop out and the missus is in the shits with me

Why do they just call it POLY? There are half a dozen "poly" plastics it could be.

Below are the things that i have painstakingly come up with and am reasonably confident of theri accuracy:

The standard bunnings ploy tube is LDPE (Low density polyethylene)
Its max safe working temperature before degredation (oxidation) is 60C
The uv stabilised used is carbon black (hence the black colour )

Also: LDPE and HDPE do not are not the same as PET, I don't believe they contain plasticisers

HDPE (like in the bulka bins) have a safe working temp of 100C (its actually higher than this, but as the melting temp is 130C.....well, you get the idea

Given that the oxidation of LDPE starts at 60C it is unlikely that it is a good choice for a solar collector unless you could guarantee that it s surface would never reach 60C. Even when not in use.

VB regarding food grade: very true, however the pvc that we are all going to use is also not certified food grade best we can do is minimize risk. food grade requires expensive and lengthy testing, as a shitty cheap irigation pipe manufactureer, why would i submit my product for testing?
Or for that matter drainage PVC? Its probably just as fine, but hasn't been submitted for the "stamp of approval"

I hope this little repository has helped someone

I'm over it, and am going to buy a tube bender (hand operated) and stainless tube!@!! Maybe i could make heat exchangers for you all LOL

THey would make great chrissy presents (just not for the wife!)

Good work Steve - confirms my thoughts.

Re the tube bender and stainless - don't want to be negative, but don't think that is going to work unless you buy a setup costing lots of thousands. Did some research on this a couple of nights back, and the general opinion seemed to be that it is just too hard for a do it at home job. Having said that, at the end of my research I think I read that anealed (sp?) stainless is easier to bend than other stuff. I should do some ringing around. Sometimes googling just doesn't suffice.

I have emailed the manufacturers of the poly pipe sold at bunnings ( find them at http://www.ppi.com.au/www/news/news20030512.html ) and asked them as to which they would suggest I use - will be interesting to see if I get a reply at all!

Good work AM!

*WAGING TAIL*
:toothy3: