The cost of the A/C unit really surprised me.
Initially I was quoted $2,900 installed. The fish room is only +/- 250 sq. ft. After discussions with my a/c contractors, we found a solution. We had the same a/c unit bought down in Puerto Penasco, Mexico (Rocky Point) and I ended up saving $1,400!!! Rocky Point is a four and a half hour drive from Tucson and we always seem to have friends going back and forth.
It is the same identical unit, however, the temperature setting is in Celsius instead of Fahrenheit. Big deal. And the instruction manual is in Spanish vs. English. I am sure that i will be able to download the manual in English. Apparently in Mexico, there are no tariffs on shipments from Japan.
Don't wanna bash you in any way, but I would never entrust thousands of dollars of livestock to el cheapo a/c.
I really don't know Mexican a/c units, but from what specs I could find online this is a cheap on/off system with 12000 BTU, using the outdated (and supposedly phased out) R22 gas.
I really don't know what units you have over there in the States, but over here in Europe only Toshiba, Daikin, Mitsubishi Heavy or Electric and evtl. Fujitsu inverters with R410 gas would come into consideration, especially because of all the heat and humidity placing the higher demand on the unit.
The physical placement is also crucial, you don't want the a/c blowing directly into your tanks or sump as the evaporation would be enormous and you would probably want to move the unit somewhere on the side, in the corner, as this would not affect the cooling effect within a closed room.
I'm also surprised by the prices you quoted, as a high-end Japanese a/c units in Europe cost around 1000-1200 euros, or up to 1500 US$.
I hope you have checked beforehand the real quality and specs of this unit and sorry if my info is completely wrong.