AngleseyPonics - Aquaponics

Aquaponics

Aquaponics

This is a system of the integration of aquaculture and hydroponics in a recirculating "closed water loop" cycle. The fish effluent (or fish waste) accumulated in the water as a by-product of an aquaculture system is collected and channelled to hydroponic grow beds where the nutrient rich fish waste (toxic to fish but rich in nitrogen and other by-products.) fertilizes the planted grow beds. This waste is referred to as "effluent”. The planted grow beds in turn digest the filtered liquid effluent thus reducing or elimininating the toxicity before it is returned to the fish tanks clean and recycled.
An Aquaponic System recycles most of the water and consumes considerably less water than other types of culture systems and is especially well suited to areas with limited water supplies. The required quantity of water needed to successfully grow fish varies with the species of fish selected, size of the unit system, and the unit process equipment design. A properly designed and operated recirculating system requires a minimum daily input of water, just enough to clean the waste from the filters and to replace water lost to evaporation.

Acwaponeg

Mae’r system hon yn integreiddio hydroponeg gydag acwafeithrin mewn cylch “dolen dŵr caeedig” sy’n ailgylchredeg. Mae elifiant pysgod (neu wastraff pysgod) sydd yn cael ei gasglu yn y dŵr fel isgynnyrch o’r system acwafeithrin yn cael ei gasglu a’i sianelu drwy’r gwlâu tyfu hydroponeg gyda gwastraff maethol y pysgod (yn wenwynig i bysgod ond yn gyfoethog mewn nitrogen ac isgynhyrchion eraill) yn ffrwythloni’r planhigion. Cyfeirir at y gwastraff hwn fel ‘elifiant’. Mae gwlâu tyfu’r planhigion yn eu tro yn treulio’r gwastraff hylif hidl gan leihau neu gael gwared ar y gwenwyn cyn iddo gael ei ddychwelyd i’r tanciau pysgod yn lân ac wedi ei ailgylchu.
Mae System Acwaponeg yn ailgylchu’r rhan fwyaf o’r dŵr ond yn defnyddio llawer llai na mathau eraill o systemau meithrin, ac mae’n arbennig o addas i ardaloedd gyda chyflenwad dŵr prin. Mae cyfaint y dŵr sydd ei angen i feithrin pysgod yn llwyddiannus yn amrywio, yn dibynnu ar rywogaeth y pysgod, maint y system uned, a dyluniad offer prosesu’r uned. Nid yw system ailgylchu sydd wedi ei ddylunio’n gywir yn defnyddio llawer o ddŵr yn ddyddiol, dim ond digon i lanhau’r ffilter ac ychwanegu dŵr os bydd rhywfaint wedi cael ei golli drwy anweddiad.

The Aquaponic Unit was up and running the late summer of 2008 – with Rainbow Trout in tanks and salad crops, brassicas and herbs in the grow beds.
There is no heating in this unit due to financial constraints and native fresh water fish are to be grown. Many plants can tolerate a cool growing temperature and we are researching to find out for how long a season we can grow and have edible produce for sale.
The aquaponic building has been built with many clear plastic roofing sheets and side panels so that there is enough sunlight for the plants. Dark green gazebo type shelters are over the trout fish tanks so that they have some shading. Any waste water is channelled into a nearby greenhouse.
This project in particular has been very much a case of trial and error and without all the help and encouragement from the folks at Backyard Aquaponics (Australia)we would have stumbled along for much longer and would probably have made far more errors along the way. Having said that – we still have much to learn and this is part of the excitement of growing fish and plants. It has helped that we had some experience in hydroponics and this has helped with the growing aspect, but the looking after fish (and trout can be quite finicky to look after) has been very much a learning curve and we have learnt an awful lot in a short time.
The sourcing of materials initially was quite a problem. Where in the UK to get fish tanks and grow beds. There appeared to be no one with aquaponic equipment! There were firms with giant aquacultural materials but these were not quite suitable for what we wanted, and also very expensive. EBay and Koi Carp equipment suppliers were watched carefully in case anything suitable for our purposes was found!
The grow beds finally came from a hydroponic supplier but these were not deep enough and we had to build untreated wooden frames covered in black plastic to make the required depth for the clay ball grow beds. We found some fish tanks and purchased three large ones holding 850gallons/3825 litres and three smaller ones holding350 gallons/1575 litres. Unfortunately the larger tanks which were made of thick black vulcanised rubber did not have flat bottoms (perhaps due to the way they were made) but we have managed to make do with them.
Two of the large fish tanks support 8 grow beds, the third large tank is holding at the time of writing 500 rainbow trout fingerlings.
The smaller tanks are used for quarantine purposes and to hold water ready to be put into the larger tanks when a water change is done.
It is anticipated that in 2009 we will also have common carp in tanks and growing water cress (for which there is an increasing demand).
The purpose of both this unit is to enable interested parties to see that produce can be grown to feed the locality without too much expense, and to hopefully help with the demand for locally grown food.
Much of the initial funding has come through the Welsh Assembly Government as an agri-innovation grant. The rest has come from us, not only with money but with the many man hours spent in research and development, trialling the different systems and finding out through trial and error what will grow in our temperate climate without adding to the cost of heating and lighting in the winter and cooling in the summer months.

How does it work?
The tank water is pumped from a submersible pump through 19mm upvc pipe to the grow beds.
Each grow bed has an isolator valve to control the flow of water through rigid 20mm pipe which is drilled at 6” (150mm) intervals.
The rigid pipes are sealed at one end and are not glued into the distribution pipe in order that they can be easily uncoupled and purged of fish goo.
Each grow bed has a19mm tank outlet to 2” (50mm) return pipe routed back by gravity to the fish tank.

To process the build up of fish effluent and rotting vegetation each grow bed has about 100 – 150 composting worms. We have not seen them since they went in!

no1_tank This our No 1 tank with trout and the grow beds with salad crops and herbs. Mid November growth This the second tank with younger plants in the grow beds