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!

Fish-Tank-Toilet

Vicki and Martin’s Place

A big thanks to Vicki and Martin for hosting Octobers Lawn to Lunch meeting in Bouldercombe!

The couple gave us a tour around their abundant garden with it’s multitude of raised garden beds and wicking beds that were in full swing with the spring food production. There is plenty of space on the property and the couple benefit from a well developed orchard and food forest that they continue to add to. Here are some photos of the day!

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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.

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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.

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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

Serendipitous Capsicum

I found a small baby capsicum sitting on the pebbles today which took me by surprise because I knew I had put in some capsicum seeds but hadn’t seen any plants. I searched around for a little while and then found this in the middle of a tomato vine, a tiny little Californian Wonder that was already starting to bear fruit. Throwing random seeds on a thickly sown pebble bed is a really exciting way to garden!

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Greg Rutter

October Meeting

The next meeting is being held at 10am on Sunday the 21st of October at Vicki and Martin’s place in Bouldercombe. Please bring a hat, chair and cup. If you don’t have the address email Greg at info@lawntolunch.org to be put on the mailing list.
Vicki and Martin live on 1 acre and have an orchard, chooks, a native plant area and no dig vegetable patch. The couple are avid bird watchers and plant to encourage birds into their garden with over 50 varieties spotted and photographed.
The integration of wild bird life works well as a pest patrol and fits beautifully into their sustainable garden.

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

Fiberglassed Beds

I got a break in the weather and found some time to start working on the raised hydroponic beds again. The picture on the left shows what I started with and the pictures below show the end result with the food grade fiberglass gel coat on the inside and a coating of cream solar guard paint on the outside.

These things are huge and can produce substantial quantities of plants especially if the seedlings are started separately before being moved to these large beds. They can also be integrated into the gardens aquaponic systems to make use of the nutrient waste that the fish are generating.

I have been aiming to redo these beds for a while as the plastic lining was not working well. Hopefully I will get the chance to do one more before the end of the holidays but there is a lot of rain forecast so it may have to be put on hold.

I will try and get this one moved into position soon to begin production of leafy greens and will be aiming to produce enough in variety and quantity to meet the greens requirements of my extended family within the next six months.


This bed is on a bit of a slope where it currently is and is collecting water from the recent rain that we have been having so I will have to move it to flatter land. The fiberglass is a food grade resin that is used in the manufacture of water tanks and is a long lasting material but needs to be left in the open for a couple of weeks to vent of any vapours while it cures.

A net fits over the top to keep out moths but I will also be making some home made light traps to try and thin them out during the spring while they are breeding.

 Greg Rutter