Aquaponics build

[Mucky_Waters]

Nice wood shed Mucky, did that take all summer to chop and stack? Mush have been tons of work I imagine.

Mitch, Are you keeping plants in the greenhouse all summer? it must be hard to keep plants indoors during the summer?
My cheap homemade greenhouse comes alive during the fall and winter, as I clean out and place succulents, lily's, and geranium plants back inside. I like just keep plants that don't get bugged as I hate to use pesticides and would rather get rid of bugged plants. Then come spring I plant seeds too, but I am quickly running out of room for all the plants I bring in these days...

Thanks Colleen. We usually go out wood cutting as a family, or at the very least I take my two boys, ages 16 and 18. In either case we generally come home with a full truck load of wood, which is just over a cord of wood. Each partition in our woodshed holds about a cord and we always make sure all partitions are filled up for the winter. Sometimes we don't use it all over the winter, like last winter, so we only had 3 partition to fill this year and we already got one load. So, at most it takes us 5 outings to fill up the shed and have more than enough wood for the winter. If nothing goes South, and we don't goof off too much, it only takes us about 4 hours to fill up the truck, but since it's a family thing we tend to goof off a lot.
Here's what a typical day of wood cutting with the family goes like.
http://www.youtube.com/watch?feature=player_detailpage&v=arDzMEDDXn0

 

[crsublette]

The aquaponic system has not been doing so great. The PH is wanting to remain stubbornly high.
I've been replacing the water change water with water from my Amazon freshwater aquarium.
Here are the parameters:

Amazon tank
PH 7.0
KH 3 dkh/53.7 ppm
GH 6 dkh/107.4 ppm
Temp 24 C/76 F

Aquaponic system
PH 8.0
KH 6 dkh//107.4 ppm
GH 12 dkh/214.8 ppm
Temp 21 C/70 F

To dilute water with 6 dKH by using source water with 3dKH, then you will have to do a tremendous volume of water changing. In my 435 gallon pond, to dilute my water from 16dkh down to 3 dKH, I literally had to fill up the pond with 80% of pure deionized reverse osmosis (diRO) water. This diRO water has 0dkh and a pH hovering in the low 5s. So, I would not be suprised by the volume of what you will need to reduce your KH. You must reduce your KH at least to around 3, if you want a pH of around 7. Also, you must use the pretreated Amazon, or low KH water, whenever doing water changes, no matter how small.

The saying of, "just let the system lower its pH over time", only applies to folk that do not have alkaline source water, that is anything around above 7ish dKH. If your source water is just alkaline enough, such as around 8dkh, then the system's pH will never reduce much at all, depending on how much of this quite alkaline source water you are using for topoffs or waterchanges.

Pre-treating water prior to pouring it into the system is very common.

Aquaponic Source is an excellent resource involve folk who do it commercially and other hobbiests that are quite successful at it.


The information I am sharing is not made out of thin air. I have learned it directly from folk who have successful systems.


I understand the apprehension, but there are certain things that can not be shruged off as it is done in the pond hobby. There is actually quite a science involved in these aquaponic systems.

 

[crsublette]

The cost of soil beds is determined by the materials used to create your own soil recipe. If you are just going to use the soil around ya, then sure it is going to be incredibly cheap. Look into wicking beds. Far more effecient at producing a bigger yield with fewer fertilizer and less water resources, although a bit pricier due to the ingredients used in making the soil and building the construction.


Also, when properly built, soil beds can control the pH better due to the acidic materials that can be used in building a soil recipe. Coconut coir is a good product to incorporate in a soil mix, although can be expensive, and it must be properly washed with a quite a high calcium solution due to the surplus of potassium and sodium in coconut coir, but, after properly treated, it has other attributes that give the Coir a pH in the low to mid 6s and this helps to control your pH by imitating a buffer.


For your bug problems, check out the Aquaponic Source. There are chemicals that are fish safe and will not harm your system that you can use to contol the insects. I have them listed in my notes, but I think it would be best for ya to check out the website.


Silica is also another primary ingredient found in soil gardens and not found in a typical "watergarden", such as aquaponics. Although, if incorporating an open looping wicking soil bed into this system, then you will gain the benefit of silica that helps to ward off insects. I had a very good article about it, but can not find it. I'll keep on looking to see if I can find it.


Hope this gives ya a direction on where to further research.

 

[crsublette]

Also, I forgot to mention, to burn off the KH, pretreating the water in a seperate container, hydrochloric acid or nitric acid is quite common to use as well.


I know there is a bit of romantacism out there about these systems, that suggests all of this micromanaging is unnecessary, which is true when growing particular crops, but, in these "watergarden" systems, the water only contains the nutrients in it that we introduce to it. They just do not suddently and sufficiently appear due to fish food.

A major reason why water changes are discouraged in these systems is that water changes dilutes the micro-nutrients and micro-nutrients is the one limiting variable that also makes these systems tough at growing particular crops. Although, water changes are still done whenever the demand arises, and, in these scenarios, the new source water is often pretreated before being introduced to the system.


The only difference between a commercial hydroponic system and an aquaponic system is the fish provides a major portion of the nitrogen. So, these aquaponic systems will have a lower nitrogen cost overhead compared to hydroponic systems, but this cost savings is replaced by the care for the fish in the aquaponic systems. As far as everything else goes, I have not yet seen an aquaponic system that is not managed like a commercial hydroponic system, except for the obvious differences.

 

[MitchM]

Thanks Charles, I knew you would bring some numbers to the party. Using RO water makes sense in the lower KH numbers regard, but then what about trace elements? Won't I have to then add back in nutrients that will raise back up the KH?
I started out replacing the aquaponics water with RO, but the plants seemed to be suffering from nutrient deficiency so I started using water fromthe Amazon tank which I fertilize.
The Aquaponics Source is where I learned the basics and ordered the bell siphons from. I've also been over to the Backyard Aquaponics forum down under.
...So many forums, so little time!

Mucky, don't worry about bringing up different topics. I kind of see these discussion threads as a bunch of us sitting around one of our ponds, chatting. People and different topics come and go. It's great.
That is a great looking wood shed! Great to hear it's a family thing too!
I'll have to try the pine maybe. BC firewood gets trucked in to a place about 50 km north of us. They bring in birch, larch and pine. My favorite so far is the larch. Burns long and hot, leaves little ash. The crazy thing is that we live on 160 acres of spruce and poplar forest. But even free poplar firewood makes for poor firewood.

Colleen, I do keep the greenhouse plants in there for the summer. I keep the greenhouse cool with shadecloths, a misting system and exhaust fan. It's on a thermostat that keeps things at maximum 27C/80F. I'm considering keeping the main doors open to the greenhouse on really hot days, but that can be a double edged sword - lets in both the bad and good bugs.

 

[crsublette]

Thanks Charles, I knew you would bring some numbers to the party. Using RO water makes sense in the lower KH numbers regard, but then what about trace elements? Won't I have to then add back in nutrients that will raise back up the KH?
I started out replacing the aquaponics water with RO, but the plants seemed to be suffering from nutrient deficiency so I started using water fromthe Amazon tank which I fertilize.
The Aquaponics Source is where I learned the basics and ordered the bell siphons from. I've also been over to the Backyard Aquaponics forum down under.
...So many forums, so little time!

Correct. diRO water is pretty much a blank slate. Regular RO water will have a higher KH than diRO water. However, with a higher pH, then the more nutrients is bound into non-soluble plant formations so then more nutrients will need to be dosed into the water.

Adding nutrients to the water is a constant. There's no way to avoid this. The only way to reduce this is by creating a wicking bed, that is put into an open looping system with your crops, using a soil mix that compensates for any nutrient loss. I am pretty sure my previous posts have mentioned this many times. This is why I am so impressed with the Earthan Group project due to the fact they have to add very little supplemental nutrients due to the soil mix used in the grow beds.

Fruits and vegetables plants consume much more nutrients out of the water than the typical pond or bog plant.

 

[MitchM]

I guess we were posting at the same time. I didn't know that water changes were discouraged in these systems. I thought they were required...
I can change that easily enough and just water the dirt plants from the amazon tank.
With wicking beds, I can see where minerals would start to crystallize on the surface. I am already seeing that on the media bed material. How is that dealt with - giving the beds a good soaking periodically from the top?

 

[crsublette]

There are only particular scenarios when water changes are required. The accumulation of sodium is the primary concern due to many garden products, plant mediums, and other products will contribute sodium.

Amazon tank water sounds perfect. If you only use this water and never use any other source water, then I bet eventually you system's pH will definitely lower.


As far as I am aware, the minerals crystallizing, that is precipitating a plant non-soluble formation, is the result of your high pH.


Also, in an ebb/flow system, you do not want the water to come all the way to the surface; the water line should be at least a couple to a few inches below the top.

 

[MitchM]

Right, I have a 1" dry zone so the bases of the plants don't get wet. It also prevents algae growth on the media surface.

 

[MitchM]

After I did about a 50% RO/DI water addition, the roses are suffering and 1 died. The vegetables and melon plants are doing better.
The water test results were not all that different afterwards:
PH 8.2
GH 11 dkh
KH 12 dkh

I think I'll stick with adding water from the Amazon tank (which I fertilize) and just give the system time to let the PH drop.
The roots from the water hyacinth and water lettuce are probably filling about 50% of the aquarium depth and seem to benefiting the most from this setup. Those floating plants have grown now to almost completely cover the surface of the fish tank.

 

[MitchM]

Update 5 months into the aquaponics project.

.
Pests have pretty much disappeared. I'm not sure what made them go away. I tried a few things over the summer - planting onions, placing spiders that I found around the house onto the media beds, spraying the plants with a diluted fish emersion fertilizer, or maybe it's just because it's that time of the year.
I've got a couple of 1000W HPS lamps that I'm going to hang over the beds soon. That will help with winter lighting and maybe radiate some heat to keep temperatures up.
I'm doing regular weekly water changes using my tropical fish tank for new aquaponics water.

Pond surface plants are doing really well. I took out the water hyacinth because it was a magnet for spider mites. Water lettuce and duckweed regularily need thinning out. I just transfer them to the outside pond. There are 8 - 4" goldfish in there (all came in as eggs on the pond surface plants), but I think I need more to help supply more nutrients



Roses and green onions (scallions) are doing well.



Herbs seem to be doing very well.
Rosemary, oregano, marjoram, basil, more green onions.



Celery is finally growing. More green onions.



Melon growth has been pretty poor. Watermelon, pumpkin, squash. Thyme is struggling since being transplanted about a month ago. More basil. I harvested the green onions that were in this bed.



In other developments, my dogs have decided that they prefer drinking aquaponics water to their regular tap water, just as they prefer the outside pond water...

 

[Waterbug]

Very nice. Do you have any nutrient test data to share?

I just thought...an interesting test would be to have some traditionally planted pots with the same types of plants next to an aquaponics grow for comparison.

 

[MitchM]

Sure, I'll get some numbers posted. I haven't been measuring because whatever the water is...is. I'm not going to muck around anymore with trying to change anything. I'm going to stick with my water change routine and whatever lives, I will focus on growing that.
I've never been able to grow basil before in dirt planted pots and the rosemary we have had for a few years. In the aquaponics system it's really taken off.
I'll see what I can do for setting up some dirt based plants. I'm pretty sure the melons would have done much better. I might try some melons again next year in the aquaponics.

 

[Waterbug]

I hear you. I hate to even take pictures. But if you had any numbers I'd always like to hear them.

The basil is interesting to me because it's one of the few plants that grows well here in Phoenix in the summer in sun, 100-110F and under 10% humidity, but it doesn't look like that type of plant. More to this plant than meets the eye.

I'm kind of resolved to being limited to tilapia and only a few kinds of plants, like maybe basil and some herbs. But having unlimited pesto would still be pretty great. Maybe if I can get a greenhouse going I could extend the types of plants because then I'd have a 7 to 8 month growing season instead of 2 to 3 months. It wouldn't hardly take any effort to keep temps up here in the winter, day time highs on the coldest days are 40-50F and always sunny.

Someday.

 

[MitchM]

Aquaponics:
GH 15 dkh/268 ppm
KH 7 dkh/125.3 ppm
Nitrate 0
PH 8.2
Phosphate 10.0 ppm + (instantly turned the deepest color on the chart)
Temp 64F

Tropical tank used for water changes
GH 6 dkh/107.4 ppm
KH 2 dkh/35.8 ppm
Nitrate 0
PH 6.4
Phosphate 0.5 ppm
Temp 71F

I was shocked to see the aquaponics phosphate number so high. I haven't tested for that before. I tend not to test for phosphate because if there is algae present, it usually takes up any phosphate anyways, making meausuring pointless. That certainly explains my strong algae growth. I don't know where it comes from though.
I've taken a handful of the media, Hydrocorn, and put it in a glass of RO/DI water which I'll test tomorrow for phosphate level. I'll be disappointed if it contributes to it.
The best expanded clay medium used to be Hydroton, but they stopped production due to lack of high quality material available.
I tried to take some Hydrocorn from the top layer that doesn't get frequent wetting. I wish I had some material fresh from the package.

The low hardness numbers from the tropical aquarium are not really representative of what I've been using for water change water. I was without C02 injection for a couple of months on the tropical tank while I waited for new injection equipment from the US. I've only got the C02 injection running again in the last 3 days.

I'll post the water test results from the Hydrocorn/RO/DI tomorrow.