Heating Water

[Two Jay]

How are you, Aquapons, heating your water?

[Two Jay]

I just posted some pictures of catfish.

Joseph Orlando said:

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!


DIV>
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.

[TCLynx]

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.

[Richard Wyman]

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$. Mine in Denver (which was much warmer) was almost 150$.

[Two Jay]

I am looking at in tank, similar to in floor, heating. Our house is heated this way, we absolutely love it and hopefully the fish will as well. With that said, I am working with a mechanical guy to figure out the efficiencies of various systems... a decision, of which system to use, will be based on energy consumption / $$, environmental impact / sustainability, longevity of equipment, reliability of system, etc.

[TCLynx]

Seems no brainer to me, if you have the funds to do a greenhouse with an insulated slab, add the hydronic heating if at all possible!!!!!!!! Ya do want an insulated slab though I think or much of that heat will be wasted heating the ground. Unless of course you are actually in an area where the year round ground temperature always exceeds your desired water temperature (like here, placing a tank in ground actually can take advantage of the warm earth but the little gain is not enough to offset cold air chilling the flood and drain media.)

If I was building a home in a location that averaged more than a week of heating days per year, I'd be planning the hydronic heating in the floors. Unfortunately, that method doesn't work for cooling, especially in a humid climate.

And Hydronic heating is very flexible as to heat sources, Solar, water heater, on demand, boiler (using whatever alternative fuels as well as regular fuels.) If ya got the budget, good choice.

[Wolfenhawke]

Faced with a similar problem -- heating water in the winter for fingerlings -- I'm going down the route similar to TCLynx recommendation. I will raise my fingerlings indoors in a fishtank that is more easily heated, and move them into their big tank outdoors in the spring when they will be a little larger.

TCLynx said:

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.

[Two Jay]

So here is a crazy, or not so crazy, idea about heating a greenhouse or the fish tanks in an AP system.

About 12 miles to the south of me and about 8 miles to the north are 2 large land fills / dumps that are generating large, large, amounts of usable methane gas.

A few months back, my wife and I were traveling past one of the dumps, at night, and I told her we should build our greenhouse there - pointing to the dump with the tall stacks of burning methane gas coming out, but she laughed and said that no one would want to buy our produce if we did that. Again, tonight, driving by, I still think it would be feasible. There are so many positive attributes about building an enclosed system at a free or nearly free power source. It would look real good to the community, showing them how "green" the dump business is running their enterprise. It would help use, useless land, the space around these structures that has to sit vacant because of contamination issues I'm guessing. To the greenhouse user, it would be a cheap steady source of heat and electric.

My brain hurts again, just a thought, throwing it out there... crazy right?

[Two Jay]

It looks kinda like this but much more low tech.

[Sylvia Bernstein]

Not crazy at all. A non-profit has formed near us (http://www.growyourownmeal.org/) who was looking to set up an aquaponics greenhouse at the city's municipal waste water treatment plant. Apparently that baby throws off some heat too. Problem is after the initial positive response from the city the city has now decided that the methane is too valuable to give away! I guess the positive result is that because of them people are now converting a waste stream...

[Two Jay]

After we get this farms greenhouse up and running I am going to make a proposal to both of the sites I mentioned and another dump approximately 40 miles away. I will keep you all posted. Turn up the heat!

[k edmonds]

I have plans to build a greenhouse with a super-insulated foundation and heated with solar water panels. My company builds insulated concrete form (ICF) homes. Essentially, ICF blocks are styrofoam blocks that lock together like legos and then are filled with concrete. I am planning to excavate about a two foot deep hole under the footprint of the green house. The sides will be insulated concrete forms which the greenhouse will sit on. On the bottom I will install plastic sheeting and 4" of high density insulation board. On top of the insulation I will lay out pex tubing which will be connected to the solar collector. The entire "basement" will then be filled with compacted fill sand and paver blocks will be installed as flooring. The way the system works, solar heated water is passed through the sand base and heat is transferred to the sand. The process would begin for me, zone 4-5, in August or September. To build up the heat it must be started well ahead of the demand. Those in warmer or colder zones would vary this start time. Heating the sand base would then continue until spring. Since everything would occur in an insulated envelope, the heat would only be able to radiate up. Insulated Concrete Forms have an effective R-value near 38-40. Actual R-values of foam and concrete are much lower than this, but when combined with the thermal transfer of heat from the existing soil by way of the concrete the value becomes much greater.
I am also looking at excavating slightly deeper and running 4" perforated tubing in the existing soil under the insulation. This would be connected to a blower system that draws the hot air of the greenhouse and pushes it through the tubing and back up into the greenhouse. The soil at this depth in summer stays around 52-55 degrees. Through the heat transfer it would be a way to cool it in the summer.

Richard Wyman said:

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$. Mine in Denver (which was much warmer) was almost 150$.

[Green Acre Aquaponics]

Of course we haven't tested this though.

Gina Cavaliero and Tonya Penick said:

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.