Yup, third the notion of removing the gourami- yes you are forcing them to live dangerously, but is it really worth it for them to be stressed out and fighting and possible one being harmed or even killed? I highly suggest giving the betta it's own tank if you are wanting to keep the gourami.
What size tank are they in? We're not here to judge or yell at you.. but would rather educate you on the proper way to care for fish- as it's for the best interest in them to help you out.
The ant farm is not a good idea, as they do need air and regular feeding- and if any escape and happen to bite a fish in it's struggle to get out of the water you could have a dead fish on your hands from the toxins the ants use when biting.
Have to keep in mind these are living creatures with specific needs such as dogs, cats, hamsters, etc.. need to give them the proper living conditions to keep them happy and healthy.