I could see an EK 280 Phoenix AIO in here, with four 120mm fans as intake (two on top, two on bottom) & the AIO set as exhaust...
Keeping in mind that one would need to shorten the tubing, add some angled fittings, & refill the loop...
Positive pressure chassis, plenty of airflow, & both intakes are filtered...!
The PSU is going to have to intake from within the chassis (to avoid it inhaling non-filtered air), and exhaust into the chassis as well (I see it mounted with L-brackets between the top & bottom front fans), but it should be alright...