I'm not sure if this is the right section to ask this question (or if I should rather have posted it on Physics stack exchange). Anyway, I'm trying to build a cloud chamber that relies on Peltier cell to cool the bottom down. I read online that the needed temperature to make the isopropyl alcohol supersaturated is by reaching a temperature difference where the colder one is about - 25/30 °C. I've tried to use a peltier TEC2 25408 or a TEC1 12708. The first one is suggested by this project (https://www.instructables.com/Peltier-Cooled-Cloud-Chamber/?amp_page=True). To cool the hot side of the Peltier down, I've tried to use a Cooler Master H412R fan, with mediocre results (the temperature I was able to reach was of about - 7°C with the TEC2 and - 11°C with the TEC1). Now I assume the problem is that the fan isn't strong enough and gets overwhelmed by The heat produced by the TEC. I thus wanted to try another kind of fan. As the previous project suggest, I was looking for a Cooler Master 412S, which, as the project I've linked demonstrates, with a TEC2, was able to reach - 40°C. Now I'm a bit skeptical about this results: do you think it is reachable such temperature? And could you recommend me some other efficient fan model?
P.S.: The fan I've talked about, the 412S, is not available on Amazon, do you think that a used one from ebay will do the work? I'm asking this because I don't know if the usage of the fan could slow it down or make it less efficient.
Thank you in advance for your answers.