Coolworks Ice Probe
http://www.marinedepot.com/CoolWorks_Ice_Probe_with_Power_Supply_Micro_Nano_Aquarium_Chillers-CoolWorks-CW1111-FICHMC-vi.html
6-8degree drop from average room temp per probe per ten gallons of water.
Check it out.. The above DIY chiller is said to have costed 175$. I've...