Main system

I should have mentioned in the earlier post that I have got the heaters running in the 4000 litre system in the big shed and the water has come up to about 25 degrees. This is costing about 10 Kwhs of electricity as expected but we have lots of spare and so it doesn't really cost anything extra. Clearly that is a nonsense as the system upgrade cost a bomb but I wanted to upgrade our power anyway and I got a 50% government grant to do so. Still nice to be able to do this sort of thing on solar power.
At this temp the fish are feeding like crazy so I will have to bit the bullet soon and try and catch some for eating.
My duckweed pond is also going very well. Lemna this time and not azolla. The fish eat about a cupful each night. I don't ever see them eating it as they are too timid but is it gone in the morning.

Another system

As you can see the plant growth in the second system is quite luxurious at the moment. This is our salad vegetables plot and at the moment we are clearly not eating enough bushes. The fish are eating very actively and I have to restrict their food intake as the GB is not really big enough for 175 fish which are up to 80mm long.

I have now finally got the third system up and running. This is supposed to be the large fish purging system but we have still not caught any of the eating size fish. I have cycled the tank, with nitrogen rich water from the black tank system, and it is now stable with a low or nil ammonia level.
This was the original planned second system but the bits didn't arrive in time and so I built the black system shown on previous posts and in the first pic of this post..

This new system has another variation on the fill and drain mechanism. I am using a bell syphon to drain the grow bed instead of the float switch and/or timer mechanisms of the previous systems.
I decided to try bell syphons because I have had problems with the other systems as I have outlined earlier.
A bell syphon is a simple device which basically allows filling to a pre set level and then an almost complete empty of the grow bed back to the fish tank. The pumps run continuously. The full flood/drain cycle takes about 14 minutes.
I tried using a single 6 watt pump but it can't fill the GB fast enough to trigger the syphon so I am running 2 of the little pumps. I bought them very cheaply on eBay some time ago and have been looking for a use ever since. The top of the bell syphon is visible in the last pic.
This growbed is being used as a part herb garden and part seedling production area. Di has already planted out the pumpkins which sprouted in the gravel.
It is really easy to start seedlings in the aquaponics gravel. Just scrape a bit of a trench and sprinkle in a few seeds and wait. Provided the weather is warm enough you get plants within a week or so. MUCH easier than the seedling mix which has to be kept moist and the beds covered etc with the old fashioned way. And no need to transplant if the initial seeding was done in a sort of even way.

A long overdue update

The last 6 months or so have been very busy for me as we have been in the process or upgrading our power supply big time. Many difficulties along the way with supply of bits. Plus the usual 1001 other jobs which need doing at the farm.
The new panels are above Phil and Ron. This picture shows an unusual weather event on 10th of October this year. Quite heavy snow for about an hour.
We have had a LOT of help from Ron Tito to accomplish this change. Actually Ron has been the driving force and without his advice and help the system upgrade wouldn't have happened.

And what has this got to do with Aquaponics you might ask?

Well..... it means lots of extra power to help me overcome some of the problems I have had with the Aquaponics systems.

The major problems I have encountered with the fish have been as simple as low water temperatures. Previous posts have detailed my efforts to get a sort of water heater going for the big fish tank. And to some degree (pun unintended) I have had some success. The lowest temperature in the big tank this winter was about 8 degrees and then only for a week or so. Last year it went down below 7 degrees and we had a couple of months below 10 degrees- and that killed all the catfish and most of the silver perch.
So the heaters worked vaguely as intended. I had to make a third one and I struggled with failing thermostatic control and cheap and nasty Rule bilge pumps but at least I haven't lost any of the fish. However another of the Rule pumps failed the other day and I decided to give up on that part of the heating system.
I have taken delivery today of 3 x 300 Watt Eheim aquarium heaters which I plan to put into the main tank in the very near future. These should be best quality if Eheim is as good as I remember from my Scullin aquarium days.
My crude calculations point to a 2 degree water temp increase for the input of 10 KwH of power. This was unthinkable before our power upgrade but we now have power to burn literally.
We have so much overcapacity now that the inverters are regulating power into the batteries as early as 10AM on most days. And we have a new wind turbine as well and wind turbines MUST have a load dump available so the fish tank will probably end up getting power from Jock as well.
Old wind turbine was Toby- a Swiss unit and Toblerone is Swiss- get it? Well Jock is a Proven wind turbine made in Scotland- so called Jock.

The other pics are of the plant growth at the moment. As you can see a bit of heat and things finally begin to grow again. We experimented with all sorts of supposedly winter plantings this year but the only things which can really cope are peas and silver beet. And the peas do really well so next winter we will probably plant all the beds to various types of them. The silver beet will stay as well as it just keeps powering on. These are now 2 year old plants which have provided a lot of chook food in that time.
We have let the lettuce go to seed just to see what happens. They grow too slowly to be much good to eat at this time of year and so the chooks benefit. They really love leggy lettuce.

And what of the big fish?
As usual I am unable to get good pictures and so you will have to believe me when I say that the biggest are probably more than 300mm long and ready to eat. I think I will try and catch them on a barbless hook. Only problem is I don't want to catch or hurt the smaller ones which are still only about 150mm long. There has been a huge variation in growth rates.

And what of the smaller system in the conservatory?
The higher minimums in this tank meant that the fish survived the winter but they haven't grown much. Now probably about 70-80mm long.
I think part of the limited growth we have experienced is due to my reluctance to feed as much as they might prefer. It has always been my philosophy that it is much better to underfeed than overfeed. Overfeeding is the quickest way to kill fish if any part of the system stumbles.

And a final pic of a fish which we found floating in the big dam in July of this year. It is a Murray Cod- about 600mm long and probably more than 10 years old. My nephew Ged gave me some mixed fish fingerlings quite a long time ago and I assume it was one of those. I was quite surprised to see this fish as we thought all the fish in the dam had died a couple of years ago when we had a big runoff event which made the water VERY muddy and probably suffocated the remaining fish.

New Fingerlings

As the fish in the main system are almost big enough to eat I decided I had to have a batch of new fish ready to put in when the big ones are gone. And as Silver Perch are really only available about this time of year I ordered 200 from Silverwater as before. I doubt they would survive with the larger fish so I had to build a new system for the little ones.
I have ordered some fibreglass tanks from Murray Hallam in Queensland but he is rather slow to respond to orders so I decided I needed to build a temporary system.

So I cut up one of the 1000 litre IBC's I had bought a year or so ago to try and water shrubs we had planted out on the farm. Not enough spare water to use them at the moment for the intended purpose anyway.
I took a saw to both the steel frame and the plastic container to produce both the fish tank of about 650 litres and the grow bed of about 350 litres from the one IBC. The grow bed needs to be about 300mm deep and that was the reason for the proportions of the split. A system with this size growbed will only support a fairly small fish load but that is the plan anyway- the fish will go to the main system long before the growbed is unable to cope with the nitrogen load.

Then I welded up a support frame for the growbed which enables it to sit over the fishtank. I also added a pine platform over the steel frame and then several layers of expanded polystyrene foam- mainly to support the odd shape of the old top of the IBC which is now the base of the growbed. I glued the screwoff lid on with silastic and cut 2 drain holes to ensure complete drainage.The growbed sits directly over the fishtank and the drains drop straight into the fish water with drain which are exactly the same as those in the big system.

I didn't mention that I also decided it had to be in the conservatory to reduce the likelihood of low temps over winter which I already know are lethal to the fish. In the time we have lived at the farm the lowest temp we have recorded in the conservatory has been about +7 degrees (when it was -7 outside) and the water in the fishtank should not go anywhere near that low point just overnight. And so I shouldn't have to build another solar heater for this setup.

After setting the system up in the front corner of the conservatory I started washing gravel. With the first system I didn't wash the gravel as it was much too big a job and we couldn't afford the water. This time I didn't want muddy water for a month and I thought it wouldn't be too big a job. Another underestimation. It took me about 3 or 4 hours to wash 300 litres of gravel. Still I did it on the lawn so the water wasn't wasted- that is now the only part of the lawn that doesn't look like straw. I also stole about 50 or 60 litres of gravel from the main system in the belief that that would get the nitrogen cycle started sooner. As it turns out I have an Ammonia level much higher than expected at the moment, in the fingerling system, so perhaps that didn't work as well as it should have.

The plan for this growbed is that it will be herb garden and Di had bought the starter plants even before I had washed the gravel- talk about pushy!!

I am using a really neat electronic timer on this system which is currently set up to run for 6 minutes 15 seconds on and 50 minutes off. Both of these times are adjustable to the second and the big benefit is that I don't have to keep the water topped up as carefully to ensure proper flooding of the growbed.
The pump is a pond pump which can move 1000 litres an hour to the head I have on this system and it only draws about 14 watts so the total power usage is very low- much less than the big system which has a pump which draws about 400 watts for 9 minutes in the hour.
The fish arrived last Thursday and look terrific- about 40-50mm long and so far I don't think I have lost a single one which is quite a surprise. And they are hungry and come to the surface to eat unlike their big brothers in the big shed. I think this is because the growbed almost completely shades the fish tank- ie no sun on the water.
I am logging temperatures and water chemistry for this system as well so I will be able to compare the performance of the two systems to some degree.

It's HOT

Today is not actually hot , in fact it is quite cool outside- about 17 degrees.
However it has been very hot this month in most of Eastern Australia.
The maximum here at the farm reached 36 degrees on 6th, 7th and 37 degrees on the 8th of Feb 09.
Fortunately we didn't reach 40 or 41 as they did in Canberra.It is always a little cooler here than in Canberra as we are at about 850 metres above sea level which is about 200 metres higher than Canberra.
The water in the fish tanks got up to a maximum of 28.7 on the 8th. Fish very active but it is at the top of their preferred temperature range.
And so I decided to turn off my little water heater as I didn't want to cook the fish just yet.
Unfortunately that turned out to be a mistake as you can see from the picture.
This is the 19mm black poly from the high point of the unit which was the heat collector for the pumped water from the fish tank.
I assume that the line didn't drain very well and the remaining water must have boiled in the tube creating steam and pressure which caused the blowout.
So I have had to make a third version of the heater. This one is basically the same as the last one.
I am getting faster at the manufacture but would prefer not to have to do it again. I think I will have to cover the whole unit with shade cloth if I need to turn it off due to higher ambient temps again.

The temperatures here have now dropped to the point where we have run the cooking stove at night- both to cook on and to heat our hot water in the house. Outside minimum last night was 6 degrees which is a huge change from the 23 degree minimum of the 8th.
And the fish tank has seen lows in the 15 to 16 degree range while the heater was broken. At these temps the fish are much less interested in food than they are at 25 to 27 degrees. There is no doubt in my mind that the heater is essential even at this time of year- even if just as a standby unit during the heatwave times.

My chillies are doing very well and are more than just decorative. The long skinny red ones , called Cayeene(?) are very prolific and Di has been using some in cooking. The label on the punnet said hot. And that is spot on. Only need one for a stir fry. According to Wikipedia it is hot:-
Heat: Hot (SR: 30,000-50,000)
It will be very interesting when we try the Habanero's which the label calls very hot. Considerable caution will be needed I think.
Wikipedia says of this type:-
Heat: Exceptionally Hot (SR: 100,000-350,000).
Habaneros thrive in hot weather. As with all peppers, the habanero does well in an area with good morning sun and in soil with an acidity level around 5-6 pH. The habanero should be watered only when dry. Overly moist soil and roots will produce bitter-tasting peppers.
I reckon I am doing most things wrong here- constant flushing with water, PH at 7.8. Looks like bitter peppers coming up. Will report on taste later. This assumes that enough can be consumed to give a taste other than fire!

The black pearls are also described as hot so I think we have good , if somewhat cautious, eating ahead. Interestingly some of the black pearls are bright red and some are black almost from the start while others start off green and gradually go black. The roundish ones in the 3rd picture are the black pearls. They have lovely purple flowers most of the time.
All the chillies were really put in because I couldn't resist the visual attraction of the plants.

We have had a bit of insect damage to some plants to date. The white cabbage moth is seen in the shed from time to time and is clear they are laying eggs. I don't have a picture of the moth grubs which are being a bit of a pest by making a feast of the asian greens. Mostly I don't have pictures because whenever I see one I feed it to the fish. And very much appreciated they are too.

We have also had something decimate one of the lettuce crops. It happened between my visits to the shed so I suspect it might have been grasshoppers. That is a guess as I didn't see any beasties. The affected plants are coming back so it is no big deal.

Fish finally growing

It is now the 19th of January 2009 and we have only had 2mm of rain for the whole month. Not surprisingly everything is looking very dry. Now 8 years of drought and little sign of improvement.
I am again very aware that this aquaponics thing has to be one of the answers to the water shortage problem. We had a new water tank installed today, up the hill behing the house, and this brings our potential fresh water storage to 63000 gallons or 285000 litres . At the moment we are at about 50% of total capacity so we are now hoping it rains soon or the lawn and gardens will really start to suffer. We have been unable to draw from the big dam for several years now.

I have to add an extra 50 litres of water a day to the aquaponics fish tank, at this time of year, to make up for evaporation. This water comes from the 22,000 litre tank attached to the big shed which has the AQ setup. I have been carefully measuring this top up water for a year and have added almost 8000 litres in that time- slightly less than I had guessed would be needed and not bad considering the fishtank holds 4000 litres.

Had a problem with my little solar water heater setup for this system. I have no idea how but the poly pipe blocked up completely and I spent hours trying to clear the blockage. Used the big pump and lots of compressed air but I was unable to budge the blockage. I could even see where the pipe was distended. Unfortunately I had done too good a job of sealing the glass top to the heater and I can't work out how to lift the quite thin glass without breaking it.
So I had to make a new heater. I had actually planned on some improvements anyway so It wasn't quite the disaster it might seem. The new one looks a lot like the old but has a layer of expanded polystyrene foam under the absorber plate this time. I used the old plate from the original HWS heater- it is aluminium and painted black. I had a few problems with the poly pipe kinking but eventually I got it to sit properly. I have covered the whole thing with a clear, very heavy duty, PVC sheet about 1 mm thick. I also added a little filter to the line after the pump. This is one of the poly ones usually put in irrigation lines to stop drippers from blocking. It is too fine for the job and requires cleaning most days so I will experiment with various alternatives. It may not really be essential as I can open the heater and simply cut and rejoin the pipe if a blockage happens again.
As far as I can tell this new heater is giving me an extra 3 or 4 degrees in the water tank each day and daily minimums are now up to the low 20s and maximums have reached 27 or 28 degrees on hot days when it have been up to 35 degrees in the shed.

This increased water temperature is what I really need for the fish and they are now growing quite rapidly. They are eating voraciously. Mostly pellets with the occasional treat of worms. The pink things in the picture are the worms from one of my worm farms.
These are the same worms I introduced to the grow beds. Somewhat surprisingly they survive and breed in the GBs despite complete flooding of the beds every hour.

The biggest fish must be close to 200mm long by now while the smallest are probably close to 90mm. The big ones could be eaten now but I feel it would be a waste while they are growing so fast. Perhaps big fat fish dinner for Easter?? I will have to set up a purging tank before then and also work out how to catch them without damage to the others.

The bushes are growing well. My chillies look great and the tat soi and pak choi are doing the right thing. We have had a lot of spinach and sugar peas. Actually the spinach goes to the chooks.
I am now quite sure that the shed doesn't get enough light but we are learning the plants which can benefit from the current setup. For example lettuce grows slowly and really isn't worth the bother as it becomes bitter when grown so slowly. Still that's another "failure" that the chooks appreciate. It's all about finding the right balance.