Thanks again, everyone. If I do decide to get a betta, I will definitely get a heater. As for my 55 gallon, I've been debating this for a while, and I've been on the verge of buying a heater many times. But I keep track of the temp, and it stays quite consistent. It stays right at 80 from April to October, sometimes climbing to 81. I add bottles of ice if it starts to get higher.
And from around November to March, it stays at 74 during the day, and drops to 73 overnight.
After thinking about this thread (and getting more advice from jpappy and 7itanium, whom I pm'd) I'll be buying a heater for my 55 to use next October, so that I can have some more control over the period from late October to early November, when the temp initially starts to shift from 80 to 74. That way, I can make sure the shift happens smoothly and gradually.
And, like I said, if I get a betta, I'll get a heater for the 20 as well, and keep the temp above 78.
And from around November to March, it stays at 74 during the day, and drops to 73 overnight.
After thinking about this thread (and getting more advice from jpappy and 7itanium, whom I pm'd) I'll be buying a heater for my 55 to use next October, so that I can have some more control over the period from late October to early November, when the temp initially starts to shift from 80 to 74. That way, I can make sure the shift happens smoothly and gradually.
And, like I said, if I get a betta, I'll get a heater for the 20 as well, and keep the temp above 78.