Thanks for your detailed reply. I like the idea of the cover over the troughs.
hey all, As an avid Ice Fisherman when I lived in Ohio, I know that Perch and Walleye can stand temps down around 36 ish. Winter ice fishing in Lake Erie is mostly for walley, and a few perch. Water depth around the Lake Erie Islands is about 32 feet. Fishing depth for those fish is usually around 25-30 feet with a few hugging the bottom. Perch are usually suspended and caught at shallower depths. The Moral? I am gonna try to find someone with small perch and/or walleye to stock with when I get to that point. In the summer, perch are the mainstay for fisherman while walleye head for the deeper parts of the lake up to the east. (60' +) The perch just head for the bottom. Plan is in place. (sigh, if only the state will see it the same way as I do)
Joseph, have you had success with your mini-hoops over your tanks? Did you use plastic, row cover, both? I'm thinking of doing that, and wondering how much it helps.
I was also thinking of trying to find a small water-source heat pump, or run a gas line from my house out there. Anyone have experience with this? I've run gas lines indoors before, but not outside or underground.
Joseph Orlando said:
For those of you using electric heaters. I will be starting with 1200 to 1500 watts to heat a 300 gal tank. However, I ran into an informative article on tank heaters. In the article it says rather than buying a 1500 watt heatter it is better to buy three 500 watt or, even better, five 300 watt heaters. The reasoning is that in case there is a failure in one heater, the others can pick up the slack until it is repaired or replaced. The are two common problems with heaters. One is total failure (no heat), the other is getting stuck open (too much heat). In either case, the other heaters will either put out more heat to compensate or lower their heat to compensate according to the temperature picked up by the controller sensors. I just thought that made a lot of sense.
Sylvia Bernstein said:I just use aquarium heaters. 200 watts heats 50ish gallons, so you just go from there. Easy, readily available, but definitely not the best way to heat a large body of water. If I could wave a wand and install whatever I wanted I would install a geo-thermal system in my greenhouse and heat the water using heated water pumped in from the earth...but that is pretty pricey!
My system is enclosed in a greenhouse which I plan to heat to about 60 degrees (I could do 70 but its cost trade off). I have bass, catfish, walleye, some goldfish and blue gill. Along with fathead minnows (which are dying at an incredible rate since temps started dropping). My sump is outside the greenhouse, partially buried and I expect it to maintain a temp of about 50 degrees through the winter. As you've pointed out grow beds are great heat exchangers. I've built an electric heater for my sump and now wondering what temp I should raise the water to... I'm horrible with thermodynamics. I'm also planning to add two 4X8 solor water heaters during the optimum dailight hours, which should give me a 20 or so degree increase in water temp eliminating the need for the electric heat for at least 6 hours or so per day. I'm doing a complete water change three times per hour. what temp would you recommend I feed back into the fish tanks?
I did what I called a solar drain heater on my aquarium system for a while. The Aquarium and grow buckets were in the spare bedroom but the sump tank was just outside the window. I set up a coil of black drinking water pipe so that the drain would send some water through that pipe when the valve was open. That could heat the water quite a bit simply laying out in the sun for part of the day. I had to remember to close the valve in the evening though as it would chill the water quite a lot at night.
The improvement of putting such a thing in a black lined glassed over enclosure would definitely make a big difference, especially if it can be placed such that it gets the best winter sun.
If one were to add thermal mass (black barrels of water or rocks or whatever) into that glassed over black enclosure, one might also use it to warm the air in the greenhouse overnight with the addition of some timer or thermostat controlled vents/fans.
I don't have a whole lot of experience in thermodynamics, but I expect if you are keeping the air temp of the greenhouse at 60 F (I really hope you are in a location where your ground temp isn't going to be sapping all your heat out of that sump tank or that you have insulated that sump tank and can put a good insulated cover over it.)
Anyway, if the greenhouse air temp is going to be kept above 60 and you expect your sump tank to stay at least 50, then you should probably be heating the water to only somewhere between that 50-60 F. If that sump tank is insulated so that you could keep the water in it pretty equal with the water in the greenhouse, then I would say you could heat the water a bit more reasonably to say 65 F which might keep your fish eating a bit more and provide more nutrients for your plants.
For those who built their own tank heater and used the ranco temp controller, what did you find worked best for your temp differential?