I have a coworker who got himself 2 betta fish and put them in bowls on his desk (I hate bowls) 1 is maybe a half gallon and the other maybe a gallon. Every time I walk past his desk I cringe . This week he's been away on vacation. He asked another coworker to feed it, but I've taken it upon myself to actually do daily water changes myself after work hours. I tested the water parameters 4 days ago. Ammonia was 4ppm! I've been doing partial water changes for the past 3 days (don't want to shock them with immediate clean water) and have gotten ammonia down to 1ppm. Hopefully this evening can be .5ppm. He comes back on Monday, but honestly I will probably just keep doing daily water changes after he leaves each evening (I don't actually know him, my studio employs 120 people) because I feel so bad for them. They both have fin rot and one looks like he may be in the early stages of dropsy . It really makes me sad.