I'm new to aquaponics and I am just starting to design a system at our new residence in San Diego. From all my research it seems like tilapia provide the fast growth and most frequent breeding however I'm worried about the temperatures and potential heating bills.
The space I have to work with is up against house so will have some insulation from the house wall, I can also turn it in to a narrow greenhouse if necessary when the temperature falls and I plan on insulating the tanks and pipes.
The reason I ask is that the CA Dept Fish & Wildlife Aquaculture Coordinator suggested that the heating bill for raising tilapia would be extremely high and suggested a non-tropical species such as bluegill, perch, bass and catfish.
I can't, though, get away from the advantages of tilapia so I'm wondering what the opinion is of any San Diego area people in aquaponics.
I am not in SD although live up the road from you in Glendora. The CADFG coordinator is somewhat right. I have both Tilapia and Bluegill in each system respectively. I going to build a greenhouse around the small Tilapia system to help keep them warm. the Bluegill system will be out in the open. There is a fish distributor near you in Alpine, and their prices are fair for the bluegill, they have a great place as I have been there recently.(yes 2-1/2 hrs there & 3 hrs back.. ugh)
Unless you are doing aquaponics to save money on food the easiest fish are Tilapia. Much more forgiving to rookie mistakes. Raising and lowering pH, ammonia spikes, etc. don't seem to affect them. I've been at it for 2 years and had good luck with them... at least until this weekend. Had a power outage and lost about 50 fish. It's amazing how fish die when they have no oxygen. Not a problem though, still have over 1000 fish. They multiply fast and easy.
Even if food cost is a concern Tilapia are a great way to learn and you can switch later if the cost is too much. There are ways to economically heat fish tanks. My tank stayed around 65-68 degrees last winter. They don't grow as fast but they do live quite well.
Use a solar water heater
I'm in Michigan and ran a 1000 watt heater 24/7 last year. That would take a lot of solar and we don't get that much sun in the winter. Cost about $90 a month in the winter months.
My system is in a GH but I only keep it just above freezing. I insulated the IBC tank and grow beds with 1" styrofoam and low tunnels last year and will be upgrading that this year to a more intense sealing of the FT. Still looking for an alternative to the bucket heater I used to heat the water last year. Going to try to utilize the wood stove a little more this year too. I have 3 400 watt HPS lights inside the tunnel and rotate their operation so only one is on at any time. This supplies plenty of heat and light to the plants and I think some residual heat to the water. Adding more insulation to the GH as well.