Everyone will say to get an engineer to come look but you seem very safe being right under that beam. I had a 180 on the 2nd floor with no issues. I had an engineer come out for my upcoming 240 gallon. He suggested supporting jacks and beams in my garage which I am adding.
I also had a 180 on a floor with a basement underneath and after 3 years I had one beam sag about 2 inches so we put in a jack and added a pole.... now my current 750 reefer sits on a concrete slab 8 inches thick... always better to overbuild if you can