If growing( hydro )in a basement....

... one of the most incredible things you can do for your reservoir is to bury it. For example, if you're doing an aerogarden ( 4" pvc , flowing back to a rubbermaid brute 44 gal.) in a basement. Keep the aero table setup on the floor (floor should consist of a plastic vapor barrier, wood deck than polyshield 3/4" foam with reflective side up , aerotable (Def. of aerotable- the 4" pvc piping that the plants are inserted into for the duration of the bloom cycle) sitting on top and pitched for drainage to the almost completely buried 44 gallon reservoir. The reservoir is buried outside(not directly underneath) of the bloom room. Just leave about 3"-4" of the top of the pail above the soil level of the cracked open ( sometimes you need a jackhammer, sometimes you don't) floor. Leave the water level inside the pail about 3" lower than your soil line just to make sure your level never goes above soil line when auto top-off control does it's thing.
Here are the 3 benefits which will undoubtedly make your life easier. 1.) The earth cools your water so well that even 250 watts worth of 24/7 submersible pumping barely makes the reservoir temperature rise above 70 no mater what time of year it is. 2.) Because your aerotable is close to the floor [this advantage being possible because the reservoir is located lower than the floor] when you put the rooted clones in place for the bloom cycle, they get ridiculous amounts of light in the beginning until all the plants get so big that they completely shade the floor, which they must do to get benefit #3.) Now that the aerotable itself is completely shaded by plants the cooling effect of the buried reservoir is not counteracted by the overhead lighting, so long as your room air intake and exhaust is located up top above the lights (1'-2' of air space above the lighting to achieve maximum cooling effect from exhaust fans). Note: You should be vigorously pumping air through the reservoir with an 8" Aluminum Oxide airstone to agitate the water so maximum cooling is achieved. Even if the air going through the airstone is warm due to ambient conditions, most of the air will enter and exit the res too fast to warm it more than the convective action of the coolness of the earth being in intimate contact with the outside of the reservoir.

this is am interesting topic, I want to ask you, where did you get this information from? is it from theoretical analysis and conclusion or was it actually tried? I am interested because I am planning to start a greenhouse hydro and I can easily bury the res in the ground if it really works that well. It also brings to mind another thought, what if one digs a cement pipe in the ground with opening far enough to cool the air going though, would this serve as to cool the greenhouse?

This is actually being done and the pics will be posted by Saturday the latest. I have 2 quiet one 6000's constantly running in the res with 6x600 watts overhead in the bloom room. I don't even bother with a thermostat any more. The water is always cool to the touch. It was a bear of a job to do the digging and the soil stunk like petroleum. Oh and I believe you have the right idea with the underground air pipe just use a conduit with good thermal convection characteristics. I once read something somewhere on the web (no link, sorry) where the guy used 8" pvc and kept going back and forth the length of the basement but he went about 5 feet down and used pvc pipe. I'd imagine you would want to use Sch.40 instead of 80. If you wanted to get crazy, you would use copper, but it would cost more than a mint. But I think there is the possibility of a calculation to determine the pipe diameter and necessary length underground according to the amount of cooling needed (ie, cfm). But now I'm just going off on a double tangent.

I've always wanted to run a pipe along side the fresh water line from the well... Well water is always cold... Put a fan drawing the air through the pipe keeping the airflow slow and steady and it will have a lot of contact time with the cool pipe (depending how far the pipe has to run)... This could work much better than a radiator style setup as, again, there is much more contact time.

I like your solution for the res, just thinking about air now.

I do like this idea. I hear people do the same thing with a tankless water heater to make a water cooled co2 generator.

I am going to switch to a tankless propane water heater to add co2 to the basement.

Free cold air in the winter for cooling lights and such. I'm hoping I will not have to run AC in the summer. It will depend how big the grow is, I guess.