Another Myth
You don't need closed loop life support to go to Mars or colonize it. You don't because Mars has plenty of resources to provide fresh input to a life support system. It has ready supplies of C, H, O, and N unlike the Moon. The Moon needs closed loop life support systems for long terrn systems because it is so very very very resource poor. It is very difficult to keep an artificial closed biosphere in balance. It is not nearly as difficult to artifically keep things in balance by expelling excess materials and bringing in fresh requirements.
Regards,
Mark