Um, didn't you just post that you have two males in one tank? Perhaps that's your problem - males are NOT ok together. Put him in his own space so the other male doesn't kill him.
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Torey
Eugene, Oregon, USA
1.1 Saharan Uros (Joe and Arthur)
3.1 Mali Uros (Spike, Turtle, Tank, and Lilly)
1.1 Ornate Uros (Scuttlebutt and Shazzbot)
0.1 Collared Lizard (Rorschach)
2.1 Green Anoles (Bowser, Sprocket, Leeloo)
1.1 Felis domesticus (Roscolux and Jenny)