Question: Getting axies soon, need advice on cooling

Hey everyone, im going to be getting a couple juvenile axolotls in a month or so, and I came up with a design for air cooling my tank with a computer fan. I have seen some other setups that blast the surface of the water with such a fan, but i dont want to do that, so I designed mine to pull the air thru the tank rather than push. I have attached a schematic and would like some input on if you guys think this would be a viable solution. My apartment goes between 65 and 75, and I just want something reliable to keep the axolotls safe.

Also I have made a checklist of things I will need, can you guys tell me if theres anything missing? Theres a respected breeder in the next town over so I'll be getting my food and axies from him.

10-20 GL aquarium
Tank Divider
Sand Substrate
Hiding places, plants, other decoration
Cooling fan
Thermometer
Supplies for water testing and maintenance

...We already have a net and a siphon for doing water changes, and I've read that filtration is not necessary as long as I do weekly water changes.

I think your idea looks fine. There is something similar listed on the Caudata Cooling page: Caudata Culture Articles - Cooling

Cause it gets so hot here a lot of Aussies have trouble cooling their tanks in the summer, I'm using a $14 fan that's sitting above the water and blasting it like you mentioned. I'm actually surprised at just how well it works and I've been able to keep the tank at a pretty constant 20.5 degrees after it hit temps around 26 degrees (my axies weren't in there at the time though, luckily.)

As for the rest of your tank setup it sounds fine. You do not need filtration but I think you'll have to regularly replace 100% of the water. For convenience sake (and perhaps your sanity), it is probably easier just to get some kind of filter, even a sponge filter of some sort (powered by a simple, cheap air pump) might be a good idea. The problem I forsee with having substrate and no filtration is that it will get filthy. Your siphon will be able to collect a lot of it but it might also collect a lot of sand which could be a pain. With mechanical filtration you'll have a lot less cleaning and maintenance to worry about.

On one of the large saltwater tanks i take care of at my college, they have a fan that sucks air out of the tank in order to cool it, however it is not as effective as the tank that has a fan blowing air at the tank. The tank also doesn't have a lid on it, so ur design might be more effective.
Not sure how much help that is

yes, the lid will be sealed off as much as possible (but still detachable) to ensure maximum airflow and evaporation across the water's surface.