So my girlfriend and I have a red-eared slider turtle. He ate our placostamus yesterday. I bought two Algae Eaters, in hopes that they would last longer. One is missing, one was found dead floating on the water. Suspects are the Zebra Danyo, the Hedgehog, and the turtle. His tank is getting quite nasty with algae and we really don't want to dump out this 20 gallon tank, wash it, then put it all back in and repeat this every 2 to 3 weeks. Is there any type of fish that is small, super fast, agile, and not DUMB enough to be stationary in front of a hungry red-eared slider who is coming right for them?