Author Archives: Rodney

Trout in Aquaponics

Posted on by

There are three main species of trout that can be used in Australian Aquaponics systems including: brook trout, brown trout, and rainbow trout.

Rainbow trout are a cool water species of salmonid which are distributed widely around the world. They have been cultured and stocked into dams and rivers in every continent except Antarctica, and are possibly the best known fresh water sporting fish in the world. Rainbow trout prefer cooler water temperatures, with optimum growing temperatures around 13˚C (56F) – 17˚C (62F). They can tolerate temperatures as low as 3˚C (38F) and as high 24˚C (75F) but not for extended periods of time.

In locations where there are wide temperature fluctuations between summer and winter, like Australia, trout can be an ideal winter crop with a really fast growing time. In areas with cooler seasons trout make an ideal all year round fish species for aquaponics.

If your going to keep trout at home in the backyard- having a larger water volume in your fish tanks will help you with less water temperature fluctuations. As the weather starts to warm up this willassist keeping them longer. Smoothing out the daily temperature fluctuations in a system makes for healthier less stressed fish, and as such less chance of diseases becoming a problem. We have also found that shading a system with shade cloth in harsh weather conditions can also aid in controlling temperature fluctuations.

Rainbow Trout in Aquaponics SystemsThis year I have kept trout in my gravity fed Aquaponics system for approximately 7 months ( since 1 March till today 29 September 2012). Today the water temperature reached 22 degrees and there was nothing I could do to lower it so I decided that enough was enough and it was time to eat them. I had planned to grow them out a little longer however with the ever increasing spring temperatures its really difficult.

This decision didn’t come lightly and only after I added shade to the Aquaponics trout tank, additional airstones, insulation to the outside of the tanks and added ice to lower the water temperature.

If you decide to try trout remember that they are quite fast growing and if you get them at the end of summer its possible to grow them out to plate size before it gets too hot if you chill the water, have plenty of oxygen and have them in insulated tanks.

Trout prefer chilled water. It would be difficult to keep them in a tank without a chiller capable of bringing the water temp from ambient down to single digit figures. That said I have kept my trout successfully in water temperatures up as high as 15 degrees. After that they start to hover around the top of the tank and won’t do well.Time to Harvest Aquaponic Rainbow Trout

They need cool well oxygenated water and unless you live under a snowy mountains dam and had flow through system I would suggest that you will either need to eat them all like I did before summer. As the amount of oxygen water can hold is proportional to temperature I suggest you add a few air stones as the temperature rises.

As you can see in the photo my trout all grow at different levels. Although the trout were purchased as fingerlings, when harvesting its clear that they all grow at differnt growth rates even though they all have been kept in the same environmental conditions. I would have liked to grow my fish for another month if possible however my biggest fish were still plate size.

What if im a Vegetarian and dont eat fish?

Posted on by

In most cases you start an aquaponics system as you wish to reuse a waste product and harvest two food commodities- both fish and vegetables. BUT- I have been asked many times what do i do if i don’t want to eat the fish in my aquaponics system? My usual response is, well it just doesn’t matter- don’t eat them im sure the fish will thank you for it. When you think about it, we only need the fish for their “waste product”to provide nutrients to our vegetables. So if your a vegetarian or if you cannot quite bring Koi can be used in Aquaponicsyourself to catch and kill your fish for consumption then why not use ornamental goldfish or koi.

There are many really strong bennifits to using ornamental fish in aquaponics systems. Koi and goldfish look fantastic, they are really hardy fish, grow really quickly and produce a great deal of waste that you can use for your vegetables. Koi and goldfish are also very tolerant of pH and temperature fluctuations.

If your going to use ornamental fish you might as well dig a pond in your backyard for a great visual effect. Its great to use recycled containers for aquaponic fish tanks but in this case you really want to view the fish. A pond can easily form a really great feature for your yard.

Silver Perch Fingerlings

Posted on by

Yesterday I received a shipment of 200, 3-4cm Silver Perch and they are now available for sale to anyone that would like to come and collect them from me. Remember its not fingerling season so its pretty rare to find any at the moment. My supplier has given me a bulk discount and breeds them with heaters over winter. silver perch fingerlings- great for aquaponic systems

Look after your fish

When you get your fish you should do everything you can keep them cool. With the rising temperatures each day the fish will suffer if you don’t handle them correctly.

  1. Simple fish transport tips
  2. Dont leave the fish bag in a parked vehicle in the sun.  You will cook them for sure.
  3. Dont leave the fish bag exposed to the sun.
  4. Dont place your fish in a fridge or freezer or cool room to lower the temperature as this will be too cold for them and they may die.
  5. Dont open the bag until you are home in your backyard and ready to add them to your tank or Aquaponics system.

Fish cannot survive long without oxygen so don’t open the bag. Try to avoid releasing your new fingerlings in the middle of a hot day. Young fingerlings or any other fish, will not be comfortable in bright sunlight or heat.  Try and release your fingerlings very early or late in the day to avoid the mid day heat and to give the little guys the best start in your new environment.

Carefully open the plastic bag so that you don’t puncture the bag. Float the bag in your fish tank for about 20 minutes to allow water temperatures to adjust.  Then after this time add a litre of your tank water into the bag to help the temperature adjustment process and also this will help with any pH balances too. Continue floating the bag for a further 5 mins and then you can release all the fish into your tank and let them swim away into the water.

If the day you intend to release your fingerlings is overcast and not too hot, you may find the above process will not be required. Temperature is the main reason for slowly mixing water. If you feel the temperature on the surface of your Aquaponic system or fish tank dam is the same or very close to the temperature of the water the fingerlings are packed in and you know that your pH is neutral, and then you may simply release the fingerlings directly from their bag into your tank after 10mins.

Another reason for the above mixing process is, when the fingerlings have been held in their bag for an extended length of time it can cause the level of carbon dioxide to build up in the packing water. In the presence of high oxygen the fingerlings can survive the high concentration of carbon dioxide, but they may go into shock if they are added too quickly to water that has normal levels of oxygen. Therefore the mixing process should be followed whenever fish have been held in bags more than 6 hours.

Port Stephens Council Aquaponics Workshop

Posted on by

Last weekend marked a great day of Aquaponics introduction training for the Port Stephens, NSW residents. This workshop gave an introduction to the principles and practical DIY methods using recycled materials to build and maintain a homemade backyard Aquaponics system.

Although the local government elections and voting got in the way, once everyone  finished that task the Aquaponic Gardener gave an great introduction to DIY backyard aquaponics technique and application. The talk focused on the need to find sustainable gardening and agriculture methods in food production to reduce food miles, increase food security and generally live in a more sustainable manner. Over 100 different styles of aquaponic systems were shown which really changed mindsets. The conversion of swimming pools and growing flowers in aquaponics were topics that had the crowd on the edge of their seat.

 see the following link for the full sustainable living program: Port Stephens Council Sustainable Living posterJuly 2012

Aquaponics is interesting

Posted on by

Aquaponics is one of the most interesting and  sustainable ways to produce fresh vegetables and fruits and, at the same time, sustain a freshwater fish system all in your backyard.

Aquaponics combines the best traits of traditional aquaculture (fish farming) and the use of water and nutrients to growing plants – hydroponics.

Koi Pond supplying nutrients to my vegetables

My Koi Pond supplying nutrients to my Aquaponics system

Many enthusiasts and professional practitioners attest to the fact that aquaponics eliminates the disadvantages of the two systems as one supports the other in a closed loop biological system.

Aquaponics also eliminates the common disadvantages of more traditional soil based vegetable gardens while improving upon existing freshwater fish farm systems. By using aquaponic techniques  both fish and vegetables  thrive as all required nutrients needed by plants are provided by the fish and will also act as a biologicial filter too.

This approach is really very sustainable and many backyard vegetable growers and fish enthusiasts around the country have already experienced great success and regularly produce fresh organic vegetables and tasty, clean fish together.

Neem Tree organic approach

Posted on by

Ever Heard Of the NEEM TREE?

The earliest documentation of neem mentioned the fruit, seeds, oil, leaves, roots and bark for their advantageous medicinal properties. These benefits are listed in the ancient documents ‘Carak- Samhita’ and ‘Susruta-Samhita’, the books at the foundation of the Indian system of natural treatment, Ayurveda. Neem has a garlic-like odor, and a bitter taste. The various parts of this tree have many uses that aptly give neem its name in Sanskrit-“sarva roga nivarini”, meaning ‘the curer of all ailments’. Some of the most important documented uses of various parts of the neem tree are:  

Neem oil is extracted from the seeds of the neem tree and has insecticidal and medicinal properties due to which it has been used for thousands of years in pest control, cosmetics, medicines, etc.

Neem seed cake (residue of neem seeds after oil extraction) when used for soil amendment or added to soil,  not only enriches the soil with organic matter but also lowers nitrogen losses by inhibiting nitrification. It also works as a nematicide.

Neem leaves are used to treat chickenpox and warts by directly applying to the skin in a paste form or by bathing in water with neem leaves. In order to increase immunity of the body, neem leaves are also taken internally in the form of neem capsules or made into a tea. The tea is traditionally taken internally to reduce fever caused by malaria. This tea is extremely bitter. It is also used to soak feet for treating various foot fungi.  It has also been reported to work against termites. In Ayurveda, neem leaves are used in curing neuromuscular pains. Neem leaves are also used in storage of grains.

Twigs of neem are also used in India and Africa as toothbrushes. Nowadays toothpastes with neem extracts are also available commercially.

Neem has anti-bacterial properties that help in fighting against skin infections such as acne, psoriasis, scabies, eczema, etc. Neem extracts also help in treating diabetes, AIDS, cancer, heart disease, herpes, allergies, ulcers, hepatitis and several other diseases.

Neem (leaf and seed) extracts have been found to be spermicidal and thus research is being conducted to use neem extracts for making contraceptives. Neem produces pain relieving, anti-inflammatory and fever reducing compounds that can aid in the healing of cuts, burns, earaches, sprains and headaches, as well as fevers.

Neem bark and roots also have medicinal properties. Bark & roots in powdered form are also used to control fleas & ticks on pets.

Neem oil, leaves and neem extracts are used to manufacture health and beauty care products. Some of such products are soaps, bath powders, shampoos, lotions and creams, toothpastes, neem leaf capsules to increase immunity and as a skin purifier, insect repellents, pet care products, etc.

Neem extracts have been approved by the U.S. Environmental Protection Agency for use on food crops. It has been proven in various research studies  that Neem is non-toxic to birds, beneficial insects or humans and protects crops from over 200 of the most costly pests

Aquaponic systems and size

Posted on by

Aquaponic type  systems can be scaled up or scaled down, totally depending on your personal production needs.  If your just producing food for a hobby you will only need a very small footprint of land however if your going to make a little income you can easily just add a few more grow beds and additional fish tanks- its really flexible. A small aquaponic system can produce up to fifty kilograms of fresh fish such as Tilapia, Murray Cod, Sleepy Cod, Jade Perch, Silver Perch or Trout or maybe  every six – 12 months  depending on the fish species used. Not to  forget the one hundred kilogram plus potential vegetable yields.

simple aquaponics IBC Tote 1 bed system

A simple aquaponics IBC Tote 1 bed system

If you want to sell organic vegetables, fruits, and fish, you can expand your operation accordingly  to produce a higher target harvests. In doing so you will need more space and a more powerful water pumps etc, but these are just one-time requirements of the system.

Once you have the expanded system in place, thats it. Just spend a few minutes each day checking for any blockages, leaks, feed your fish and your laughing. All you have to do at that point in time is to maintain the system so all your plants and fish grow well. aquaponics systems can provide abundant harvests on a day-to-day basis.

Remember: no one is too old or too inexperienced to start their own aquaponics system. If the desire to be self-sufficient is there and you have the passion to get things done, aquaponics is definitely right for you!

Living elements in Aquaponics Systems

Posted on by

Aquaponics has four major living organisims- Fish, Plants, Bacteria  and Worms. In fact the humble worm is a key component of a thriving Aquaponics set up. Add a few handfulls to  each of your gravel grow beds for fast sucess. Worms play a key role in decomposing fish and plant waste that accumulates in the gravel grow beds. Worms both take advantage of this material and release the mineralsback into the system for plant use, and also keep the gravel beds free from clogging. A system with worms will never need cleaning. A system with out the little guys may need to be cleaned every year. 

Worms can thrive in very wet conditions assuming they are provided with some oxygen.  As worms love moisture your providing the ultimate habitat, since apart from the high moisture, worms would also greatly appreciate the rich microbial buffet laid out before them. Add to this the fact that worm bi-products have been shown time and time again (via academic studies) to help stimulate plant growth via and it seems like a no-brainer to stock a grow bed with them for sucess. Yet its suprising how many people dont do it.