Fish time

Today I got my fish.   I am starting off with a small number to test the system.  I got 32 4"-6" Channle catfish.  They were $1.50 each  I also stoped at the local feed store and got a 50# bag of feed for $23.

      I am using Channel cats because they are common in aquaculture and live well in most water conditions and tempratures.   I also like to eat catfish yum, yum.   I figure that my system could hold 100 to 150 fish total but I dont want to stock that many before I know that it will work.   This way I can test the system without the large investment for that many fish.   The plants I started will need the nutrents from the fish very soon or they wont grow.

growing setup

I have made a floating grow system.  It is a 2'x4'x2" sheet of insulation foam.  I went to a local Hydroponics store and bought some mesh pots for it.  Being the first time I have tried  this setup I am not sure about the spacing of the pots or the size  that is best to use.  I have 15  three inch pots, 5 four inch pots, and 3 five inch pots. I filled the pots with washed pea gravel.  So far I have planted chard, spinach, basil, brockaly, and chives in the floating system.  I planted watercress in the top of my bio filter where it is doing very well even with so few fish in the system.   I also made a grow tub out of a cement mixing tub from the hardware store.  I filled it with pea gravel and put a timed pump on it so that the water would rise and fall in the tub to let air down to the roots of the plants growing there.  I am going to try tomatoes also but I don't know how well they will do in the system.  I am starting out with mostly green leafy plants because I have a green house over this whole setup and it will keep out most of the polinators that would be needed for flowering plants. I will try to hand polinate but I dont know how well that will work.

Aquaculture fish food and cost

What do you feed your fish.  I have given this alot of thought.  This depends alot on what kind of fish you have.  If you have Tilapia you can get away with not feeding them and they will still grow off of algae in the water.  You could also feed them all kinds of green waste, like grass clippings.
Most other fish are carnivores and need more protein rich food.  There are many commercial manufactures of fish food in pellet form.  My local feed barn sells some for $32 for a 50 lb. bag. Now if you consider that with fish a 2 to 1 average feed ratio is bad (2 lbs food for 1 lb fish growth) and a 1.5 to 1 is common then 50 lbs of food will get you about 25 lbs of fish.  If you are talking catfish, about $7 per lb at the store.  25 lbs of fish would cost $175.  Thats a big difference.  There are other costs of corse not just food but it still works out to less than half the price for good nutritious fish.
    Other fish foods:
Worms,  You could start a worm farm.  Worms grow fast and live on vegetable wast.  They are also good fish food.  Red worms per 100 grams  84% moisture 2% ash 11% protein 2% fat 2% other.
Crickets,  I dont know about growing crickets but they would work if you could grow them fast enough.
Crickets per 100 grams, 75% moisture 1% ash 17 % protein 6% fat 1% other.
House fly's,  This is perhaps the best, although not the most appetizing idea for feeding fish.  The house fly has good nutritional value and is very easy to breed.  Breeding like jackrabbits would be the understatement of the century when it comes to fly's. 2 fly's could become hundreds of millions of fly's within 3 weeks.  For more information see Kurt Saxons "The Fantastic Fly" article.  I have been thinking of a small version of his fly house.  Set on the side of the rearing tank it would supplement the fish feed nicely.
      I have recently heard about Black soldier fly larva as a fish food.  It is probably the best that there is.  They grow fast, eat almost everything and best of all self harvest.  Look them up for more details.  I am starting a a BSF bin ASAP.
I think that with any alternative feed some production feed should be given also to balance the vitamin intake of your fish.

The biofilter is a 55 gallon drum with the plastic irrigation pipe media.  There is a 3" drain pipe that goes down to the bottom with notches cut in the end for water flow.  The water splashes down to the the water level and gets lots of air mixed in. Then it flows up through the media and out a drain into the pool.  The drain is set in such a way as to cause a circular flow in the pool.  This is called an up flow filter I think.

Biofilter media

The bio filter gave me some trouble mostly on what to use as media. As anyone who has looked knows media is very expensive form $8 to $20 per gallon.  When you need 35 to 40 gallons of it the cost is outrageous. I think I came up with a solution that should work and was cheep. What I ended up with is scrap black irrigation pipe of various sizes from .5" to 2.5" cut into about .5" rings on a band saw.  This pipe floats and is cheap. It offers a lot of free space and surface area.  I have about 35 gallons of this material in the Bio filter drum.  It took about 3 hours to cut it all up and wash it off. When you make this with a bandsaw you will end up with alot of little black plastic shavings.  It will take a long time to remove all of them.  However they do float and can be netted out of the tank with a pool net.

Swimming pool system

I have set out to build an home Aquaculture system. I have wanted to and studied for years to start this system and I finally got the chance. The idea is to raise fish in a small above ground pool. What I have now is a 10' by about 2' Intec pool from Walmart. I have two 55 gallon drums one is for solids and the other is a biofilter. The whole system should run on a 500 - 1000 gallon per hour pump. I am going to start with about 50 catfish in the 4" range. This is a small quantity of fish but I want to work the bugs out as I go. This is what I have so far.