After only a day or two of Tadpole ICU, I found two tads on the floor of the tank.
This was so upsetting. Was I now going to have to helplessly watch them die off one by one, as they seemed to be doing outside? I’d had the water tested for everything, more than once, so I knew that wasn’t the problem.
I filled their Tiny Tank with water from their Big Tank outside, so they wouldn’t be shocked by a change in bacteria or temperature. I asked at the fish store — they were helpful with my indoor setup but mystified about the deaths. (They specialize in fish, not tadpoles.) The pond & water-garden store people, who have provided me with tadpoles in years where I didn’t get any eggs, know literally everything about these frogs — except this. They seemed as puzzled as I was.
By coinkidink, my Other Three-Quarters was reading a book called Simple Fountains, by Dorcas Adkins. She came across the following simple paragraph in a sidebar entitled Stocking Limits. “You don’t want to overstock reservoirs with animals that can’t simply get up and leave overcrowded situations, such as fish and tadpoles. A good rule of thumb is to allow 3 gallons (11 liters) per inch (2.5 cm) of aquatic creature.”
I am horrified. This alone could well be the problem — which would explain not only this death of the masses, but others occurring in previous years. And now it seems so obvious. Why didn’t I think of it before?
We did the math. According to that equation, these half-inch creatures need a gallon and a half of water each — meaning that this five-and-a-half gallon tank could accommodate three or four tadpoles. That might explain why two of the fifteen died right away, and why the population of the Tiny Tank has since dwindled to ten since I put them in there. Are six more of them doomed to die?
And all of this means that my outside tank — of thirty-five gallons — can accommodate twenty-three tadpoles. Not a hundred.
I might be a frog murderer — rather a far cry from being the Jane Goodall of tree frogs.