Sunday, February 3, 2013

Aquaponics Opinion and Information

 Where to begin? There really is a lot of info on the web about AP. So much that like anything it can be overwhelming at first and make even a simple task of selecting a pump complicated. I will try to break it down in what my opinion are good places/items/plans to start with. Along with opinion, I will throw some facts and info out there. ;-)

Ok, first things first. When I first started I looked at all kinds of websites and all kinds of youtube vids on different systems. There are some that are really complicated and produce a massive amount of food and there are some, like mine, that are small(ish) and produce enough food for my needs.

 You have to decide how much food you want to grow and how much space you want to dedicate to it. You also need to decide how much you want to invest, at the start, on something you may not like, or ever be able to figure out.

 I always recommend that people start small and upscale later on. It is far easier to play with and dial in a 20 gallon system vs. a 200 gallon system. I don't want to scare you off, because the concept is really simple, but there are some things that will drive you crazy. So, know before you go, try to keep cost down and use, reuse whatever you have lying around. You can literally make a system out of two 5 gallon buckets.

Design: Look before you buy. When I say look I don't mean look at kits or prefab ponds and such. I mean look at what other people have built and listen to what they say about it. What would they have done differently and what they love/hate.

 You can build the typical flood/drain system, and ebb/flow system, over/under system, a tower system (my next project) or a gutter type system...using actual gutter or PVC pipe. I am not against kits per say, I think it's great that people are making good money off these things, but I am kinda against how blah they are. 

I have seen systems made from storage totes, barrels, plywood and tarps, kiddie pools and fish tanks to prefab standard tank kits with custom stands and all.

 As a side note, if you are thinking about incorporating a greenhouse into the system at some point, include the feature in the design stage. Make sure it is removable, and easily so. This way, instead of planning and installing around plants and weather, you have a ready made system that attaches with ease.

 Now that you have figured out what size and type of system you want, you need to decide on a medium. There are basically two types: Clay balls, and everything else. The clay balls look nice and neat and from what I have seen they perform well. I know some of them float and that can be an issue depending on your system. I have seen grow beds filled with everything from the clay balls to lava rock to broken Terra-cottar pots. I wanted more surface area for the bacteria to harbor, feed and produce nitrates/nitrogen so I went with lava rock. It was a personal choice and as long as you stay away from things like asphalt and concrete chunks you should be fine. Just don't use wood or anything that can/will rot or mold.

 First question. Do you plan on eating them?
 Second question. Do you want them to be "pretty"?

 If you don't plan on eating them, then just buy goldfish or koi. They eat and poop a lot, they are hardy and they are nice to look at. Their cost effectiveness is ideal when buying several dozen "feeders" to condition your system. A second plus side is, about 40% will survive and live in the environment for a long time and can grow pretty big. They can be eaten, after all, they are just pretty carp.

 If you plan to eat them, then you options are pretty close to limitless. I am not sure where in the bay you live, but it really doesn't matter that much. You don't have to worry about snow in the winter or 110 degree temps everyday in the summer. To heat the water in the winter, you can either use an aquarium heater, or utilize the heat from your pump. (See pumps)

Tilapia - Very popular with the aquaponics community, mainly due to the availability, proliferation and hardiness. There are some restrictions in California for breeding or transporting tilapia, so be sure to check the fish and game regs before you buy. I think you can only possess whites or goldens as they "die" when the temp dips below 50 degrees. You may also be limited to purchasing triploid or "sterile" breeds.

Trout - They taste great, but are a fairly sensitive fish. Water temps must stay below 65 degrees or they develop gill rot and die.

Bass, bluegill, crappie and catfish - All taste great, if they are prepared right. All are hardy species that winter well in Ca. All species are known to spawn at least once per year and sometimes twice depending on habitat and water temps.

Carp - Hey they are a staple fish in the rest of the world so why not? Very hardy, grow large, but their breeding habits can be finicky.

 Their are some restrictions on the type of fish you can "grow" in Ca so be sure to check regs before you buy. There are several "fish farms" that you can buy from, but some will require a permit from DFG before they sell to you.

Feeding: Hopefully you won't be like me and have an inconsistent feeding schedule. Feed them as often as they will eat. I use worms, slugs, grubs, bugs, fish flakes, krill and krill pellets. I also feed them cooked rice and bread occasionally. Every once in a while I will buy a few dozen rosy reds or feeder goldfish. A few days after I do this, I notice a growth spurt in the plants.

 The more you feed them, the more they poop and the more plant food your system can make. This is probably chief among the reasons to have a high pump volume capacity. Turn that water, filter the solids and ammonia, make that nitrogen.


Buy more pump than you need. Trust me. (But not so much that you blow pipes and fittings out)

 To submerse, or not to submerse, that is the question. Personally, I chose not to have a submersible pump, for a few reasons. I got the pumps for free. If you use a submersible pump then you have to have a separate heater if growing warm weather fish, like tilapia. If you use an external pump the pump itself will provide some heat to the water as it cycles through the impeller. It is not much, but during these last few weeks we have had lows in the 20's and hard freezes and I haven't lost a fish or a plant. Also, my water temp did not drop below 50 degrees.

 In addition to heat and cost, you should use a bucket or other container to house the submersible pump. You should never place the pump directly on the bottom of the tank for two reasons: solid matter plugging up the pump and a break in the drain outflow. If you have a submersed pump without a container and have a break in the lines while you are away or sleeping, the pump will drain the entire system of water, kill your fish, possibly your plants and maybe burn up.

 A submersible pump does have a few benefits though, one being cost as they are usually cheaper than and external. The other being availability. You can buy submersible pond pumps at any garden store, practically all big box retailers and often find them for cheap on Craigslist. Also, you do not have to worry about priming a submersible pump, which can be a pain. (Filling the pump and pipe lines with water to create a suction at start up)

 But, again it is all about preference.

 One thing to take into account is the amount of water your system will contain and the amount of "head" or height the water has to be pushed by the pump. You want to turn your tank at least once per hour to promote bacteria growth, increase dissolved O2 and keep water clarity at peak. So if you have a 200 gallon system and need to push the water up 3-5 feet, you will need a pump that has a GPH rating of 200 @ 5' of head. Regardless of what anyone will tell you, it is never a bad thing to turn your tank more than once per hour.  Mine are turned between four and five times per hour. So on a 60 water gallon system turned four to five times per hour equates to 240-300 gallons per hour @ 5' of head. And that is after the flow has been restricted by 1/3, not by the use of ball valves, but by decreasing pipe diameter. (See plumbing)

So you can see now why I said to buy more pump than you need. You can also restrict the flow of the pump by using ball valves at various points in your plumbing system. You will need to do this anyway when you fine tune your siphon. (See bell siphon)

Oh yeah, use some type of solid matter filter. A sponge, a sock, some sand, etc.

Again it's all preference and necessity based on system size, pump size/type and volume. You can use PVC or pieces of cut up garden hose. The basic plan should be created when you are planning the actual build. This will help you to think through any placement issues with pipe and power, as well as drainage options and placement.

 Two suggestions though:
 If you are not using a submersible pump, then place your drainage pipes about 4-6 inches off of the bottom of the tank. By doing this you will prevent a failure in the pump, plumbing or siphon from completely draining your tank.
 Use unions at critical junctures if using PVC or other solid pipe. This will help if you need to take the system apart to fix or change the design.

 You want your water to be clean, clear and with a healthy supply of ammonia chomping bacteria to produce healthy plants and fish. It also needs to be the right temp and have the appropriate PH for the plants you are growing.

 The flow and cycle will depend largely on your system size and design, as well as the pump volume. Once you get the system up and running, it will mostly take care of itself in terms of ammonia, nitrogen, PH and clarity. There are tweaks and adjustments that you will make daily or weekly for a while, but once you get it going good, you shouldn't have to to anything to the water, except add more once in a while.

Bell Siphon:
 I use a bell siphon for my drain needs. It is a simple concept, but it does require some work to install and then fine tune to your system and volume.

The construct is an inner tube that is contained by a capped outer tube, or "bell". When the water fills up the bed and outer tube, it begins to run over, then into and down the inner tube. This is where the cap on the outer tube comes in to play. Once the water starts to flow down through the inner tube it pulls any air left in the outer tube out with it. Once all the air is "vacuumed" out of the tube the siphon begins in earnest.

 The cycle can be kept going indefinitely, assuming some adjustments have been made. Meaning, unless you set a point on the outer tube, at which the siphon will automatically break, it will continue to trickle forever once the main volume of water has been siphoned.

 In the video you will see the notches cut into the lower portion of the outer tube. This is the set point that allows the siphon to break automatically. When the water level reaches a notch it allows air to flow back into the bell, thus breaking the siphon. Understanding exactly how the bell siphon works, is key to designing it and tuning it.

 I watched almost all of Affnan's videos on youtube and there is another guy in India that was very, very creative and resourceful in his design and set up.

 Some people use an air hose as the siphon break and some people use notches. Either will work. Below is a really good video on the bell siphon. I only wish it was available when I built my system.

 That is all I can think of for now. I will try to take a quick vid or two of my current system and email them to you. Let me know if you have any questions about anything here or something I may have missed.

Good luck and have fun,