Ken and I went to the local pet store today and bought some tiny cherry barbs for the small aquarium. To do so we had to move the 6" angelfish from that tank to the larger. Which was not easy, nor was it fun. Hopefully (s)he'll be happier with more plant cover and more room to cruise around in.
I also had to buy a new heater. I don't need the expense but the one we had was not adjustable and I found that it was simply too powerful for the 15g aquarium and because we have cool-water fish in the other tank it was not going to work there, either.
Some day. I'll have a 50g tank or something of the sort, and need a special 30 amp circuit just for the many heaters, filters, etc.