Your tank reminds me of these paludariums I found on youtube.
Black nosed dace?Tank update: The hydraulic cement has spiked the pH this time around, so just waiting for it to come down. Other than that I've decided to switch from a banded killifish/mummichog tank to black nosed tank. I found a little stream down the road with them which is a nice little spot to collect. Once the pH is corrected I'm going to try to get some to put in.