Well, actually, I was talking about exactly what I described in my post.
However, I do remember one year a long time ago I had just moved into a lakehouse on a beautiful pristine lake. My second night there I caught a catfish fishing from my dock. Knowing I had someone coming to visit that weekend I took the catfish, whole and put it in the freezer. It was in there overnight. The next day, as a joke, I filled the bathtub and put the frozen 5 lb catfish in the tub, knowing my visitor would want to shower after the trip. After my guest arrived, we talked over some coffee for about an hour and then, as I expected, requested the shower. I waited for the scream and got exactly what I wanted....I rushed in as though I was surprised and wound up being more surprised than my guest. The catfish was alive and well splashing around wanting out of the tub!
No actually, fingerlings don't necessarily survive cold better. Now this all depends on what kind of cold you are talking about and what kind of fish.
That would surprise me too, (that the catfish survived a night in the freezer only to come back to life in the tub that is) but I suppose I would be startled to find a 5 lb catfish in some ones bath when I went to take a shower.
Anyway, I would recommend doing some further research, especially if you are planning tilapia fingerlings, for the overwintering of small fingerlings in a cool environment. I'd always understood that you get best growth from tilapia if you give them a good start with high protein feed for their first couple months which might be difficult if it's too cold for them to eat.
However, small tilapia fingerlings could be overwintered indoors in an aquarium with a filter and just do some water changes with the outdoor system to keep the nitrates in check and reduce heating costs. Then just a little heating in spring to get the outdoor system up to a similar temp as the aquarium when it comes time to transfer the fish.
Has anyone thought about radiant floor heating in a greenhouse? Though the initial investment would be a bit high it could be a good solution to heating in cooler areas. I haven't done much serious research on putting one in a greenhouse, but it sure seems like a slab slightly larger than your tank area would heat tank water and the air around it together to minimize the condensation problem.It can also be used with many different energy sources.
My Mother's new house has gas water heaters heating her floor, and in April, in Gunnison Colorado (still freezing at night) she had a combined electric and gas bill of 38$. Mine in Denver (which was much warmer) was almost 150$.
We are thinking about building a glass encloser of sorts with old surplus sliding glass doors or cheap surplus windows. We will paint the inside black, and run black irrigation pipe into coils.We will then tie into those pipes with a bypass line so the water runs through this before it returns to the fish tank. With this set up, and the tanks getting insulated, it should more than sufficiantly heat up the water throughout the day to stay warm through the night.
Nikki said:I have been wondering the same thing. We are just starting out and will be going pretty basic initially. Pretty much, we'll be starting with the old fashioned fish in a barrel...probably catfish. Beyond painting it black and putting it in the sun, I have no other ideas besides the water heaters in heating the water. I would definately be interested to hear the other ideas out there. Something economical and sustainable.