System design

[Sylvia Bernstein]

What are your thoughts on system design?  Media vs raft.  Deep media beds vs shallow.  Siphons vs timers.  Tell us your thoughts and let's get the conversation rolling

[Jeffrey Walls]

Because I have a fairly large settling tank (roughly half the size of the culture tank) I don't have much of a problem with clogging. Occasionally a piece of gunk will get in the distribution tube but because the crops rotate fairly frequently (lettuce, spinach, etc. ) I examine each site pretty regularly. The tube is 1/2" pvc with 1/8 inch holes drilled at each site. Bio-buildup usually shoots right through as it is under pretty good pressure.

Even if one or two holes do plug it is not the end of the world because the roots dangle down to the film and the remaining holes and other facets of aeration are sufficient.

Before the settling tank however........................

[Jeffrey Walls]

No worries! :-) I am going out now to check on the system I will snap a few pics to show you what I have.

Emma Lysyk said:

Oh! Thanks. I probably should have guessed that... Forgive me, I haven't had my morning coffee, yet.

Jeffrey Walls said:

Nutrient Film Technique. The roots are exposed to nutrients via a thin layer of liquid passed along the bottom of a pipe or gutter type grow tube.

[Jeff Givan]

We live out in the desert and the sun can can be brutal to say the least. One area I am not sure on is shade cloth. I know enough to know I need it, but what percentage do I want to block out. These products come in as low as 22% all the way to 90%. Anyone have any good suggestions other than go talk to locals that have used it?

[TCLynx]

The truth is you might want different % for different purposes and times of year. In summer here I definitely need it mid day and could probably have a higher % than I do but in winter, I'm better off removing it. I wound up going with 40% aluminet to let in more light but hopefully block a little more heat.

Over the fish tanks, I used fencing wire for safety and then I put netting or shade cloth to keep leaves out of the tank and on top of that I often have a piece of black fabric to block most light from the tank.

At some point you will probably just have to make your best guess about what will be most appropriate to your situation. Think about what types of plants you will be growing (some things are more affected by extreme sun and other things will suffer with more shade.) It will also depend on your methods since most people keep like things together in a raft but if you use gravel beds you might mix taller sun loving plants with smaller ones that prefer more shade so the bigger ones will provide the shade and allow you to use a lower % shade cloth.

Good luck making the choice.

[Jeff Givan]

TC your amazing! I appreciate all your help and insight!

TCLynx said:

The truth is you might want different % for different purposes and times of year. In summer here I definitely need it mid day and could probably have a higher % than I do but in winter, I'm better off removing it. I wound up going with 40% aluminet to let in more light but hopefully block a little more heat.

Over the fish tanks, I used fencing wire for safety and then I put netting or shade cloth to keep leaves out of the tank and on top of that I often have a piece of black fabric to block most light from the tank.

At some point you will probably just have to make your best guess about what will be most appropriate to your situation. Think about what types of plants you will be growing (some things are more affected by extreme sun and other things will suffer with more shade.) It will also depend on your methods since most people keep like things together in a raft but if you use gravel beds you might mix taller sun loving plants with smaller ones that prefer more shade so the bigger ones will provide the shade and allow you to use a lower % shade cloth.

Good luck making the choice.

[Shawn]

Aloha- I read through this forum and thought it would be the appropriate place to put up some details on my system, as it is a little unique. I'm at about 4000' elevation on the Big Island of Hawaii, and it can get pretty chilly, and we get 80-100 inches of rain annually. That's great for keeping a system topped off with free water (my entire community is without county water lines- each residence harvests their own household water from the rain), but it's very acidic rain, not at least because we are just a few miles from one of the worlds most active volcanoes, steadily spewing sulfur dioxide into the air. Anyway- in order to balance the pH of my 10'x12'x24" pond, I lined it with ferrocement, which is basically brick mortar with a little more raw cement added, and applied to wire mesh. After my first fill a few weeks ago with water that was below pH 6, it balanced out to nearly pH8 within a few days. Already it is starting to drop down to a sensible 7 as more rain flushes through it- the ferrocement will be leaching a lot of lime in it's initial post-cure life. So it looks like a very sensible system if you have acidic water.

The other system details are as follows:

• Flood and drain system.
• Pond is a hole dug in ground, approx. 10x12' and varying in depth from 18" to 36" in one deep corner. Lined with ferrocement with 1/4" mesh reinforcement.
• A 3/4hp, 13 gpm Grundfos pump delivers pond water to the grow bed every 30 minutes. Fill time is just under 3 minutes
• Grow bed is 18"Wx8'Lx11" deep (2x12 lumber frame with plywood bottom, also lined with ferrocement and filled with locally quarried volcanic cinder (a fine medium with it's porosity, and it's free!)
• Grow bed drains through a 1/2" PVC line to the pond. Drain time is about 10 minutes.
• Since the system is in my backyard, I also want it to look nice, so hence the pond instead of a tank. There is much pondscaping yet to be done, however.

The pond does not have any fish in it yet, as it is all coming together just now. I had a successful desktop system last year with a 10 gallon aquarium and a rubbermaid grow bed, to get mey feet wet with Aquaponics. Now I'm jumping in with grand style. I found this forum through Sylvia's blog in a search for aquaponics info at wordpress.com, and I already love it. Backyard Aquaponics is great, but agree with Sylvia in that it is a little overwhelming, and not totally applicable to those of us in the Northern half of the earth. At least Hawaii is somewhere between!

I hope to get more pics of my system up soon, but do let me know if you have any suggestions or questions...

Shawn

[Sylvia Bernstein]

Aloha, Shawn. Thanks for sharing the details of your system - sounds to me like you are off to a great start! When do the fish go in? How did you cycle it? You might want to get in touch with Jeff Givan in this community who is from Southern CA and has also integrated an aquaponics system into his landscaping. Looking forward to the photos!

Sylvia

Shawn said:

Aloha- I read through this forum and thought it would be the appropriate place to put up some details on my system, as it is a little unique. I'm at about 4000' elevation on the Big Island of Hawaii, and it can get pretty chilly, and we get 80-100 inches of rain annually. That's great for keeping a system topped off with free water (my entire community is without county water lines- each residence harvests their own household water from the rain), but it's very acidic rain, not at least because we are just a few miles from one of the worlds most active volcanoes, steadily spewing sulfur dioxide into the air. Anyway- in order to balance the pH of my 10'x12'x24" pond, I lined it with ferrocement, which is basically brick mortar with a little more raw cement added, and applied to wire mesh. After my first fill a few weeks ago with water that was below pH 6, it balanced out to nearly pH8 within a few days. Already it is starting to drop down to a sensible 7 as more rain flushes through it- the ferrocement will be leaching a lot of lime in it's initial post-cure life. So it looks like a very sensible system if you have acidic water.

The other system details are as follows:

• Flood and drain system.
• Pond is a hole dug in ground, approx. 10x12' and varying in depth from 18" to 36" in one deep corner. Lined with ferrocement with 1/4" mesh reinforcement.
• A 3/4hp, 13 gpm Grundfos pump delivers pond water to the grow bed every 30 minutes. Fill time is just under 3 minutes
• Grow bed is 18"Wx8'Lx11" deep (2x12 lumber frame with plywood bottom, also lined with ferrocement and filled with locally quarried volcanic cinder (a fine medium with it's porosity, and it's free!)
• Grow bed drains through a 1/2" PVC line to the pond. Drain time is about 10 minutes.
• Since the system is in my backyard, I also want it to look nice, so hence the pond instead of a tank. There is much pondscaping yet to be done, however.

The pond does not have any fish in it yet, as it is all coming together just now. I had a successful desktop system last year with a 10 gallon aquarium and a rubbermaid grow bed, to get mey feet wet with Aquaponics. Now I'm jumping in with grand style. I found this forum through Sylvia's blog in a search for aquaponics info at wordpress.com, and I already love it. Backyard Aquaponics is great, but agree with Sylvia in that it is a little overwhelming, and not totally applicable to those of us in the Northern half of the earth. At least Hawaii is somewhere between!

I hope to get more pics of my system up soon, but do let me know if you have any suggestions or questions...

Shawn

[Jeff Givan]

Aloha Shawn! Welcome to this great community! Sounds like you have a great system and will be interested to hear how its going as you integrate it all. This group will help with anything you need, just don't hesitate to ask.

Sylvia Bernstein said:

Aloha, Shawn. Thanks for sharing the details of your system - sounds to me like you are off to a great start! When do the fish go in? How did you cycle it? You might want to get in touch with Jeff Givan in this community who is from Southern CA and has also integrated an aquaponics system into his landscaping. Looking forward to the photos!

Sylvia

Shawn said:

Aloha- I read through this forum and thought it would be the appropriate place to put up some details on my system, as it is a little unique. I'm at about 4000' elevation on the Big Island of Hawaii, and it can get pretty chilly, and we get 80-100 inches of rain annually. That's great for keeping a system topped off with free water (my entire community is without county water lines- each residence harvests their own household water from the rain), but it's very acidic rain, not at least because we are just a few miles from one of the worlds most active volcanoes, steadily spewing sulfur dioxide into the air. Anyway- in order to balance the pH of my 10'x12'x24" pond, I lined it with ferrocement, which is basically brick mortar with a little more raw cement added, and applied to wire mesh. After my first fill a few weeks ago with water that was below pH 6, it balanced out to nearly pH8 within a few days. Already it is starting to drop down to a sensible 7 as more rain flushes through it- the ferrocement will be leaching a lot of lime in it's initial post-cure life. So it looks like a very sensible system if you have acidic water.

The other system details are as follows:

• Flood and drain system.
• Pond is a hole dug in ground, approx. 10x12' and varying in depth from 18" to 36" in one deep corner. Lined with ferrocement with 1/4" mesh reinforcement.
• A 3/4hp, 13 gpm Grundfos pump delivers pond water to the grow bed every 30 minutes. Fill time is just under 3 minutes
• Grow bed is 18"Wx8'Lx11" deep (2x12 lumber frame with plywood bottom, also lined with ferrocement and filled with locally quarried volcanic cinder (a fine medium with it's porosity, and it's free!)
• Grow bed drains through a 1/2" PVC line to the pond. Drain time is about 10 minutes.
• Since the system is in my backyard, I also want it to look nice, so hence the pond instead of a tank. There is much pondscaping yet to be done, however.

The pond does not have any fish in it yet, as it is all coming together just now. I had a successful desktop system last year with a 10 gallon aquarium and a rubbermaid grow bed, to get mey feet wet with Aquaponics. Now I'm jumping in with grand style. I found this forum through Sylvia's blog in a search for aquaponics info at wordpress.com, and I already love it. Backyard Aquaponics is great, but agree with Sylvia in that it is a little overwhelming, and not totally applicable to those of us in the Northern half of the earth. At least Hawaii is somewhere between!

I hope to get more pics of my system up soon, but do let me know if you have any suggestions or questions...

Shawn

[Shawn]

Ah yeah, I forgot to mention a few details. I have 10 small comets and 15 baby koi in a brooding tank, but in the next few days my boys and I are going to try to capture some feral koi in a stream in Hilo. They get washed out of people's ponds in heavy rains or get dumped. There's also a huge population of aquarium fish there. Some of the koi are quite big and quite fancy, and they seem pretty healthy. Eventually I want to set up a tank to raise food fish, but I don't like Tilapia, so I am trying to figure out if I can get yellow perch or bluegill.

The pump is controlled by Indigo (smarthome software for Macs) and x10 hardware. The pump is plugged into the x10 switch and I have the scheme set to turn on every half hour, and then automatically shut off after running for 2.75 minutes, but only during daylight hours. The pump is too close to our bedroom, and I need to insulate the pump house for sound before I can run it all night.

Which brings up a question: How long can I expect bacteria to survive between flood cycles? I know some people don't even cycle at all at night, but would that kill off bacteria.? Also- what about temperature for bacteria? Our nighttime temps get down to mid 40's sometimes in winter, but more typically mid 50's, and low 60's in summer (4000' elevation, remember!)

Sylvia Bernstein said:

Aloha, Shawn. Thanks for sharing the details of your system - sounds to me like you are off to a great start! When do the fish go in? How did you cycle it? You might want to get in touch with Jeff Givan in this community who is from Southern CA and has also integrated an aquaponics system into his landscaping. Looking forward to the photos!

Sylvia

[TCLynx]

How long can bacteria go without a flood. The bacteria can survive as long as it doesn't dry out completely or starve too long, overnight shouldn't be a problem for the bacteria as long as the system is not heavily stocked. However, during initial cycling up of a system, I would advise running it more often rather than less, you want to build up your bacteria colony and running the system often, even constant can help that.

If the weather is warm and the system heavily stocked and fish eating well, the fish might not do well with the system being shut down overnight. When things are going full tilt, the ammonia could build up quickly and the fish might not thank you then.

Temperatures. Well, our night time temperatures can get even colder than that in winter and my system is still ticking along ok. If your system is heavily stocked and you get a cold snap that manages to chill your water down below 50 F, you might want to watch your ammonia and especially nitrite levels for a bit after that to make sure you don't get any spikes but I expect you will be ok on that score. Night time temps in the 40's and 50's sounds like really good growing weather to me.

[Shawn]

That's all good news, TCLynx- thanks. I just amended my pump schedule to run until midnight, and then on again at dawn, so that is only about 6 hours of off-time. I just added some of my India Blue worms to the bed, with some of the casings, and threw in a very dirty household water filter from our catchment system to try to kick start the bacteria. The bed is covered with a sheet of plexiglass to warm things up a bit, and I hope to actually use the warm bed to heat the pond water up a little bit. Right now it's at about 60 deg F.

To bring this back to the subject of system design, I run the pump so intermittently because I'm really keen to balance power consumption with efficient plant and fish growth. I don't want to run a pump and bubbler 24/7 because that is simply a significant carbon footprint that may not balance out. I accept that my yields will not be maxed out, but I feel strongly that I can meet our needs. The fish will be the most susceptible to crisis, so that is my baseline- finding the maximum amount of fish that the system can support. I'll be starting with info I found on this site: 5lbs of fish per 25lbs of GB media. That gives me a starting point of 15lbs, so I'm hoping to catch 5 or 6 medium sized koi tomorrow! As I add more beds, I'll add more fish.

Thanks for all the advice already, this is quickly becoming one of my favorite sites to check each day...

TCLynx said:

How long can bacteria go without a flood. The bacteria can survive as long as it doesn't dry out completely or starve too long, overnight shouldn't be a problem for the bacteria as long as the system is not heavily stocked. However, during initial cycling up of a system, I would advise running it more often rather than less, you want to build up your bacteria colony and running the system often, even constant can help that.
If the weather is warm and the system heavily stocked and fish eating well, the fish might not do well with the system being shut down overnight. When things are going full tilt, the ammonia could build up quickly and the fish might not thank you then.
Temperatures. Well, our night time temperatures can get even colder than that in winter and my system is still ticking along ok. If your system is heavily stocked and you get a cold snap that manages to chill your water down below 50 F, you might want to watch your ammonia and especially nitrite levels for a bit after that to make sure you don't get any spikes but I expect you will be ok on that score. Night time temps in the 40's and 50's sounds like really good growing weather to me.

[TCLynx]

Once your system is cycled up, you can definitely reduce the amount of pumping to find where a good balance is, however, while you are cycling and when you first add fish, that is not the time to push the envelope. It takes a good 6 weeks to get a system cycled up with a good bacteria colony.