Aquaponics Trellising

I have pulled out everything that was growing at the end of Autumn and have started to prepare all the new infrastructure to hopefully have it ready by the start of spring. I did start some seeds but it has been so cold that the only seedlings that have even taken have been the climbing beans and one of the varieties of tomato. I am not worried about this as there is so much that has to be completed by spring.

I will be starting on the moving all of the aquaponics equipment into one location over the next week and have just finished putting up all the trellising which will hold the tomatoes, cucumbers and pumpkins when the warm weather returns. Rick gave me a large amount of heavy wire netting to put on the frames and I just need to work out how I can transfer the larger sheets home to finish the project off.

The steel was all rescued on its way to the dump so it has really only cost the price of the paint and some fencing clamps to get it all together.

Recirculating Wicking Beds

I am currently modifying a number of my flood and drain gravel aquaponics beds into recirculating wicking beds just to see if there is any improvement in the productivity of the tubs over standard aquaponics. RWB’s are similar to normal continuous flow gravel beds allowing water to flow through the stone media at the base to assist in the conversion of ammonia into nitrites and nitrates.

The top part of the bed however is a soil layer which wicks the water up from the base. The overflow pipe is placed just below webbing material which separates the stone and soil layers. I have no idea how this will work out so I am only trying it on a few beds until I can iron out and problems and see if there really is any advantage.

Tomato Trees

I love these photos I came across a plant that people were calling a tomato tree. There are lots of photos on the net of what appears to be a well trellised variety of indeterminate tomato vine. I am not sure of the particular varieties used so I ordered seeds of a few different types that people said create this kind of display and have started the seeds in my recirculating wicking beds.

The top picture shows a trellised tomato vine on display at the Epcot centre in the US and is supported by a series of steel poles like you would use with a chain link fence.  This has been an inspiration for me as I acquired a large amount of free steel poles from an old shade shelter that was being pulled down at the state school. The poles were full lengths and galvanised so there is very little rust on them. The first ones that I put up were bolted to the concrete base that supports the main crayfish tank and the fibreglass grow beds. I found however that the poles snuggly fit over the top of a star picket which is allowing me to extend the trellised area out over the other grow beds without having to concrete the bases into the ground. If I need to move them later I can unbolt the fittings and lift the poles off of the star pickets.

Papyrus and Duckweed

The sun is pretty harsh in Central Queensland and the problem that I keep facing with outdoor tanks are the algal blooms that take over and smother everything. I have been told that the aquaculture researchers at CQU say not to worry about this as it doesn’t affect the fish but I think that it looks appalling and can’t be good for the hygiene of the system. On one of the tanks I covered it with a wooden lid but this is not a good solution for the larger AP tanks so I played around with it until I got the following solution.

This tank was seeded with miniature Papyrus and duckweed. The duckweed covers the total surface except for and area over where the air bubbler is placed. The duckweed reduces evaporation and cuts down the amount of sunlight getting into the tank. Next I added a one off hit of barley straw extract to get the existing algae under control and finally I added a large number of Swordtails and Guppies that I got from Peter D and Bill M which are doing a really good job of cleaning up any new algae that forms.

This tank will be used as a redclaw growout tank but I see no reason why Jade and Silver perch can’t be added as they don’t tend to eat fish the size of swordtails.

The Miniature Papyrus is an excellent tank cover plant as you can spread it by just cutting a piece off and dropping it into a new location. The Papyrus forms a floating mat that gives the Swordtails babies plenty of room to develop and doesn’t take up space in the tank for the rest of the fish as it floats on the surface.

IBC Aquaponics

Judie’s Uncle Ron, has recently gotten the Aquaponics bug after a relative first introduced the idea to him a few years back. Starting with four IBC containers Ron has begun setting up a number of flood and drain grow beds and several wicking beds at his and wife Lorraine’s Berserker property.

The beds have been repurposed from second hand storage containers that previously contained non toxic materials. At the moment Ron is using ornamental fish to condition the gravel growbeds but is looking to introduce perch within a few months.

Greg

Trevor’s Hydroponics

Judies grandfather, Trevor Morgan, sadly passed away recently so I wanted to post this tribute to him with some photos of his wonderful and brilliantly constructed home hydroponics system.

I was really grateful to have had the chance to meet Trevor several times and really hit it off with a kindred creative spirit. Trev, you will be dearly missed.

If anyone is interest in purchasing this system please contact me and I will pass your offers on to Trevor’s widow.

YSHS Aquaponics

Yeppoon State High School has been branching into the field of aquaponics and is teaching students about this budding area of agriculture with an interesting program in the school that integrates hydroponics into their existing aquaculture system.

The entire system is housed under cover with artificial lighting so that all the elements can be controlled for the students to experiment with. YSHS staff Charlie and Tamara have been working on building a number of different hydroponic systems that students can use to learn about the pros and cons of different Hydroponic and Aquaponic growing techniques and the results that the kids have come up with have been outstanding.

The plant production is tied back into the aquaculture system with Barramundi and red claw generating the nutrients the run the system.

Wicking Bed Winter Greens

I got the first lot of winter greens into the wicking beds. These are mostly a mix of Asian greens like Choy Sum and Bok Choy and Evergreen Bunching Shallots. Next year I will start the first seedlings a lot earlier as they grow pretty well as soon as the really hot weather is finished. I will start a new lot of seedlings every two weeks to be ready to take over from the maturing ones.

I have 4 six square meter raised wicking beds now but only one of them has been fibre glassed on the inside so the others rely on a plastic liner which I have found to be unsatisfactory for this purpose. I still have a large quantity of Fibreglass matting and will get to work soon to seal another one of the beds. I have found that once the raised trampoline beds are fibre glassed then there is very little maintenance needed in looking after them and they can grow out as many vegies as you would get in a much larger area if you were just planting seedlings straight into the soil.

The biggest problem that I have had in the past has always been with the cabbage moth caterpillars which don’t  just take one or two of the plants but all of them in one foul swoop. This year I am ready however with a combination of pest netting and Dipel spraying to keep the bugs at bay. Dipel is considered an organic treatment and doesn’t harm other creatures including non target insects. It is a trademarked name for the BT bacteria which gets into the stomach of the young caterpillars and causes them to stop eating.

Another run to drain system!

Following up on my article about run to drain aquaculture I thought I would share this small scale internally plumbed version of the concept!

Just like our larger outdoor version the concept is the same. No need for a water filter just flush and fill!

Incorporating Aquaculture into Orchards

Mixing aquaculture into the management of fruit trees was an after thought for me but has worked so well that I think it is worth considering for anyone who has a small orchard as it improves the nutrient quality of the water and creates an additional by-product of fish whilst giving water a second use and removing it’s chlorine which adversely affects the soil microbial life. 

When most people consider adding edible fish to their backyards they immediately think of aquaponics as the only way to do this, the problem is that as much fun as aquaponics is it can be a difficult learning curve and I have seen a lot of people who have tried it and then given it up when it became too hard or they lost some fish. You do have to enjoy the tinkering involved with keeping a system balanced and healthy and it can become a full time hobby in itself.

A much simpler alternative that can produce just as much fish and similar vegetable hauls is to use simple run to drain aquaculture by setting up a water tank to house your fish in and then using that tank for all the watering that you were already doing in you’re yard.

Once you have finished watering top you’re tank up again and the fish will be just as happy as if you had scrubbed their water clean with aquaponic flood and drain grow beds. This method works particularly well as a water/nutrient supplier for fruit trees and if you incorporate a large number of wicking beds then you are able to get similar water efficiencies to aquaponics at a far smaller cost especially if you were able to pick up a free water tank and patch any holes it might have which is my preferred tank acquisition method.

The picture below shows where I have added a through-tank tap fitting that will take a regular garden hose to one of my tanks. The water is gravity feed out to the plants and just trickles out the other end at a slow rate which means that none of the water is wasted as it has time to filter into the ground around the roots of the plants without running off. When I am working in the yard I just go over occasionally and move the hose to a new location.

 

It is ABSOLUTELY ESSENTIAL that you put the tap fitting no lower then half way up the tank otherwise you may one day forget that you left it on and all your fish will die. The other important thing to remember is that the air lines must be placed right at the bottom of your tank otherwise the fish will run out of oxygen when the waterline falls below their air bubbler level. 

You should also select a hardy fish species that is use to rising and falling water levels and living in small pools of water whilst they wait for the next Aussie wet season to hit. I use Jade and Silver perch but Sleepy cod might also be a good choice. I don’t believe that this technique would work with Barramundi but have never tried it. Spangled perch are likely to breed in tanks but I haven’t tried those either and don’t know what they taste like.

One other thing that you must add is some sort of backup air supply in case the power fails. This can either be a backup bubbler or bilge pump that sprays the surface or a solenoid valve connected to mains water that gently but vigorously sprays the surface of the tank to break the surface tension.

The return water inlet that tops the tank backup with water can also have a float valve like in a toilet that switches the town water off once the tank has been filled up again. I preferred to take out what water I need before turning on the tap to refill the tank as it reduces that amount of chlorinated water that makes it to the plants. The inlet valve must be at the top of the water tank to prevent the tank from being syphoned dry if the connecting hose is removed from the mains water tap.

With a bit of scrounging your aquaculture watering tank can end up costing very little money and certainly much less then many aquaponic systems  and if done properly there is no reason why you should be using anymore water than you would have before with your regular plant watering schedule the only difference will be that the water will be much better for the trees!

There is one caveat that I must include about directly filling your tank with town water. It is well known in aquaponic circles that adding town water directly into an aquaponics system is a major no-no. The reason for this is that chlorine in the water will kill off the bacteria that is necessary in the nitrification cycle of the system. This means that the plants will grow less vigorously and the ammonia won’t get taken out of the closed loop system which will end up killing the fish. This is not a problem if you are using a run to drain system however as you are not dependent on recycling the water for the health of the system. You must however consider if the level of chorine will have any impact on the fish in your tank. I live in a small town that is a very long way from the water treatment plant in Rockhampton and the chorine levels seem substantially diminished by the time they reach us. I have done a large number of cycles of the tank without any losses of the fish due to water quality.

I have also noticed that the fish feed much more vigorously after the water has been changed and it seems to have gotten rid of some fluke parasites that were in my aquaponic fish before I started adding the chlorinated water to the tank.

If you are concerned about the levels of chlorine in the water then you should use an intermediate dechlorination tank, even a cheap food grade IBC container will do the job. It doesn’t take long for the chorine in town water to evaporate off especially if the water is spayed into the tank as a fine mist.

Greg Rutter

Bathtub alley comes of age

Bathtub alley has left behind it's steam punk roots and adopted a more gentrified appearance in recent days. The grand plan for the garden calls for something that is not only functional and productive but also aesthetically pleasing.

Time is always the enemy however and most of these things end up being postponed until holiday time when I have the luxury of idleness to ponder what might be.

 The top watering system is working much better then the flood and drain method I was using before and allows me to start plants directly in the pebble mix as seeds.

The regular over head showering also helps to cool everything down when the weather starts to get hot. An Arduino based timer control lets me set when water should be provided so that the plants always have some time to dry out after each watering.

The plants that I am concentrating on in this area are tomatoes, beans, shallots, leaks, cucumbers and capsicum.

I have put some corn in but mainly just to help sop up the excess nitrogen as they are fairly hungry feeders. Most corn production is done in the fiberglass beds attached to the green tank which can turn out about 150 cobs at a time.

The bathtubs will be the permanent infrastructure in this zone but I am also considering other ways of taking advantage of the large nutrient store of the cray tank with things such as mobile bucket racks for tomatoes that get water pumped up to them and then drain it back into the tank with a gravity feed. These racks would be able to be moved around for mowing or disconnected if no longer needed.

















Greg Rutter

There's plenty of fish in the tank

The green tank was the first fish tank that I put in a couple of years ago and I think that I have severely overestimated the amount of fish that a small group of people would actually need. In the two main tanks there is now about a quarter of a ton of fish with the majority weighing in between the 1 and 2 kg mark.

One of the great things about Jade and Silver perch is that they are mostly herbivorous and won't eat their own young so it makes it really easy to maintain a constantly staggered production of fish by adding another hundred fingerlings to the tanks as you start to eat the larger ones.

I am ordering a fish smoker and will try it out with both the jades and silvers as I have read that these are exceptionally good fish for smoking.

So far we have only been frying the fish and have to be careful to purge the fish for a while as they can get very fatty.

I think that the main problems are that I am over feeding them and also using Barramundi feed (They didn't have bulk Perch food at the time and gave me Barra pellets for the same price) which is too high in protein.

I may start to mix their diets up a bit more with a lot more leafy greens which they love and only a small amount of pellets. Articles that I have been reading indicate that the oiliness is an advantage when smoking but so I will see how that goes.

I really want to make changes to the green tank as I made a few mistakes when setting it up. It would be nice to empty it and re-seat it on a concrete base instead of crusher dust and also raise the fiberglass grow-bed's that do all the corn production so that I can get a more reliable performance out of the auto-siphons that drain the water to the sump.

These guys really kick up a storm when you throw food in the tank. They will eat at any time of day but put on a really good show in the early morning or just on dusk.

I will take a few out this week and see if they are carrying to much body fat. They don't eat as much during winter and tend to be a lot leaner by the start of spring.

Greg Rutter