Backyard Aquaponics
A place to discuss aquaponics

Maybe if thngs go well, they'll be getting boxes that say your name on the box....
Oh wait, you've got Tilapia, er, assorted african cichlids....
Some of them might just fall out of the tank and onto the grill!

I'll have to set up a corporation in Nevada so I can have my address from there and charge shipping -- I suspect shipping costs at least as much as the fish.
It probably annoys the pet stores -- I walk in and study their fish for hours and rarely spend any money. And then I ask the hardest questions like -- "Is that really a convict cichlid in that tank?" Or "Which one is the Jack Dempsey." "Did you notice that you have 14 koi floating upside down in your tank?"

I set up two more GB's last night. one was a styro raft on top of my 10 gallon. Drilled about 15 1 3/8" holes in a 2" styrofoam chunk and slipped seedinlings in peat pellets into the holes. Hopefully the peat won't acidify the water too much.

And then I had a brainwave. I've been wanting a cheap, lightweight grow media for my indoor growbeds. I found a big bag of styrofoam peanuts that I have saved from my Ebay purchases. I filled the bottom part of the growbeds with peanuts and then put some paper towels on top (to keep the gravel from falling to the bottom) and dumped a little perlite and gravel and clay balls on top (to keep it from floating when I flood the bed. I'll upload pictures when I get a chance.

I had a bit of fun with my fish last night. I fed them a spaghetti noodle.

http://www.vimeo.com/clip:165320

What does a cichlid fingerling cost in AK?

Between 6 and $40 depending on size, and variety

$6 minimum...wow. I sell my Tilapia fingerlings to the pet store for $2 each and they sell them for $4 each since they are rare still in the cichlid world. I sold two 6" males to the fish store for $15 apiece and they went out the door for $38 and $45 (one was very colorful). Next time I will charge $20 wholesale.

Do they have Tilapia at the LFS where you are?

I saw a cichlid that looked amazingly like my tilapia but I'm not sure. There are several tropical fish stores (Walmart doesn't count) in the area. I haven't studied all of them.

If they do have tilapia at the LFS, they won't know it.

OK, it looks like one of the fish is definitely a male. His head is pink, body has very few markings. Tail has vertical stripes and he has dug out a hole in the gravel. He alternates between chasing all the fish away from his "nest" and trying to herd them towards it.

Give him a flower pot on its side, and he will stake that out and dig in front of it. That may also help limit the size of his territory, giving the other fish more room to retreat from him. A man has to have his Love Shack, after all.

I spent two hours in front of my aquarium trying to figure out which ones were males and which were females. I haven't figured it out, but perhaps they are not all mature.

ems, I just read all 12 pages of your topic in one sitting. Great stuff. I have a partitioned concrete tank in Michigan. The foundation of the tank is down 48" (42" frost line here - all perminent structures must have foundation below frost line). My tank is 24'x6'x6' outside dimensions - poured 8" thick walls with a partition making an 15' section and a 7' section. The tank is 6' deep 3' in ground. It is rectangular. I sprayed the interior with the only organic sealer I could find - it is used for selaing floors against Radon gas.
The advice about ferrocement is largely from warm climate people. There are many cold climate concerns. Freeze/thaw cycles move the earth with hugh pressures. We only get -10f here and I put 2" foam around my tank and the tank wall is inside an outer layer of 2" foam. The ground under my solar greenhouse never gets below 48F. The concrete is a 6 bag mix done in one continuous pour by professionals. The floor is poured first with rebar sticking up for wall connection. Also a ribbed vinyl strip is embedded in the floor up into the walls to prevent leaks at the floor/wall seam. The tank holds water very well. I know the vinyl was needed because the divider between tanks did not have the vinyl and water seeps between tanks (if I only fill one, the other fills slowly thru the seperator wall). Without all these precautions, you could end up with a tank that seeps water continuously and needs lots of water makeup. As a cold climate dweller you might want to do some local checking before making a large concrete tank. Do people have poured concrete basements in your area? Does the ground shift with freeze/thaw? When I was at Denali they said they had permafrost at some depth. You are further south, but do you? Will -40 suck all the heat out of your buried tank? Were you planning foam insulation around the tank?

I had never heard of the foam/bubble insulation technique. Thanks! Time to do some reading. I like Hayden's idea of a third layer providing an air film to protect the buble layer.

What are you going to do during the dark months? How much lighting wattage do you need? What kind of lighting are you planning?

I agree with you that using an ordinary gas water heater is the way to go. As I understand it, ordinary water heaters are steel tanks and perhaps glass lined (I think I heard that). Pull out the zinc bar and go! If they were copper they would cost thousands these days. I heard (not sure) that they replaced zinc with aluminum or something because zinc was too expensive. Lowest setting of water heater may be more than you want. If so, then feed a smaller flow of warmed water into top end of raft system and it will be cooler when it gets to the fish tank.

My whole system is raft with net pots. You might want to use stand pipes in the raft beds to maintain a minimum level. Have more than one exit pipe and lots of overcapacity on output end. With flood/drain at unsynchronized times and possible root clogging of exit pipes, you do not want a big overflow flood.

I can tell you are well researched and learning more every day. You have a lot to contribute and I will be watching your posts with great interest.

I must disagree with your idea of patents. You may think a 2x4 or a brick have value but ideas should be free. I have the opposite valuation. Ideas are the most valuable commodity. They advance civilization waaay more than working hard 'the same old way'. Some people, like Thomas Edison, have made a living finding better ways to do things and owning the rights to things they have invested time and money developing. Everyone is totally free to give away their ideas. Others should certainly have the right to profit from ideas they have spent time and effort developing. I am an engineer and consultant and a one man corporation. My ideas put food on the table. It does bother me when anyone says ideas should be free and I have no exclusive right to produce what I invent. I give away ideas here, but reserve the right to keep those I choose. If you read my signature line, then you know I am not a socialist. The idea of sacrificing the few for the benefit of the many is enslavement of the few. No more soap box, but I can not leave the 'patents have been misused' statement go unchallenged. Patents keep people from stealing ideas like other laws keep people from stealing bricks. The ideas are much more valuable and important. Artists need the same protection. Creations are valuable and need protecting, even more than bricks and other tangibles. More than enough said on this.

Hello EMS and Doug,

On the note of ground heaving from freezing in regards to concrete and foundations, EMS, you may be interested to read a bit about the concept of FPSF (Frost Protected Shallow Foundation). It has been used very effectively in houses where deep frostlines make normal foundations very expensive, keeping costs down dramaically, while protecting from heaving.
Try here: http://oikos.com/esb/43/foundations.html

also DL a pdf here: http://www.pathnet.org/sp.asp?id=9039

Hayden, that system is not yet accepted in my area. Too bad, it works perfectly. I have concrete to below the frost line and 2" foam outside the foundation - that meets our code here. This isolates the concrete of the foundation to be a thermal mass added to the interior. With the large amount of concrete in the tank, floor, and foundation, the greenhouse will stay above freezing without any artificial (expensive) heat source. With a small amount added using natural gas heater, the plants and catfish&bluegill do well year round.