IceProbe Thermoelectric Aq. Chiller (Coolworks)

[Cyclonite]

You will need 3 more than likely, insulate really good and it makes a huge difference.

[debritto]

This is the cheepest I've found out there its for 55 gallon or less.

http://www.thatpetplace.com/Products.../Itemdy00.aspx

[Cyclonite]

I don't think the drop will be more than say 4 or 5 degrees from ambient temps with 55gal

[GluteusMaximus]

I think there are a couple things you should consider before you decide on how much cooling you really need.

If you have a 55 gal reservoir, then you obviously have a significant volume to cool. The real question is....how long does the water remain inside the reservoir between cycles? If you're using a flood and drain and you're feeding 48 containers from that 55 gal reservoir on a very frequent basis, then the volume of water will heat quickly when the water cycles into the containers and won't have much time to cool while in the reservoir. The longer the water remains in the containers will greatly influence how much heat is absorbed into the water before returning to the reservoir.

You should insulate your reservoir (Water Heater Blanket) as well as your containers (if possible). If you're using bucket containers, then place plastic over the rocks preventing light and heat exposure to the grow medium (plastic picnic plates work well). Another trick is to put a (small) fan blowing across the top of the water inside the reservoir. This will remove heat through evaporation. You will find yourself topping off the reservoir more frequently, however, the evaporation trick will lower the temps significantly. You should attempt as many of these tricks before you invest in cooling devices. This way you'll save as much as possible by purchasing only what you need.

Lastly, 58F is way too cold. Idealy, you want your reservoir temperature to be at 68F.

[Cyclonite]

Yea I keep mine at 65 (DWC)....Its sooo much easier than putting in frozen bottles and shit. The deal with the fan is yes it will cool it down fine but then it makes more work and who likes that....make sure light doesn't travel down the fan air path, gotta top off res more often, it may introduce some nasties into you nute mix and with the evaporation if you don't keep a close eye on it your PPM could go way up and burn plants possibly. I don't even really open my res besides changing it....I ozonate the new water going into the container to kill of the crap wait 30-40min dump in my nutes and bam I'm done. I had some problems since the ice bottles float the roots could lay on them and could cause damage.

[debritto]

I took one of the vent covers off the light hood to install ducting to an inline fan, but the fan was too loud for me so, I disconnected it. I left the vent cover off and wow it really cooled down the room a lot! So, I took the cover off the other side too!

I have a 9 gallon aeroponic system. The 55 gallon tank is in reference to the iceprobe's max compacity. Thanks again.