Pond Boss Forums AERATION Systems questions Fountains sffect on water temp?

I Have a 1-1/2 acre new pond in Michigan. I Definitely intend to put in an aeration system but lately have been wondering about supplementing the usual bottom up air stone mixer with a fountain which I could time for night time use. Here's my thought and I'm wondering if anyone else might have tried it and quantified the effect.

Night time temps in mich. are typically about 15 deg F cooler at night than in the day to start with. Spraying hot pond surface water (say 80 deg F) into the air in small droplets will have a cooling effect by evaporating some of the sprayed water; (latent heat of evaporation), and perhaps by air to water droplet conduction and convection at times when the air temp is lower than the water droplet temp. In theory this should be in the right direction for cooling pond surface water.

My interest here is in preserving cold water temp at the bottom of the pond (20' deep, and 60 Deg F), so I can keep some trout alive. I would still do some bottom up circulation to provide Oxygen at the bottom, and would have to experiment to get the right balance? Maybe a thermostatically controlled operation?

Anyone tried it?

TMK, I used a submersible pump 2 years ago, before I had an aerator. It was in 3 ft of water with a 6 ft pvc pipe attached and homemade nozzle to spray the water like a fountain.
It was on a timer so it would only run at night, so I'm sure it helped to cool the pond, but the fountain pump will use alot more electricity than an aerator.
If the extra cost is not a factor I would say a fountain would be a good addition.

TMK, As you do your research on a bottom diffused aeration system consider adding 5 ft risers to your discs to create a cold water refuge. Also size a system that has a regulator built in that will allow you to slow the system down. You will want to know the operating range for the air station. For example if a station has a range of 1-2.5 cfm be sure to stay in that range. If you go below that minimum you will still have bubbles but very little verticle current.For trout ponds a good DO meter is a great tool also.

TMK, I have designed systems to do just what you are looking to acheieve. We supplemented a bottom aeration system designed just as Ted is describing above and at night ran a Display Aerator on the surface to cool the surface temps.

We have done this in ME, CT and NY for trout. We were able to drop the surface temps close to 10 degrees overnight.

Cary Martin, Can you give me anymore details? How big are the ponds you have equipped for this purpose? What is the optimum spray pattern? GPM/unit surface area? Etc? I am especially interested in the cut off temperature (water Temp vs Air temp) when such a system will not work, and when it works best?

Your web site is very large. Can you point me in the right direction for the appropriate equipment?

Wow! 10 degrees overnight... That is impressive, would certainly make the trout happier!