If you have a Russian Tortoise and In your email message you said you were lowering the water level ( big no no)Russian tortoises should have a water dish available for them 2-3 times a week, a shallow dish that they may or may not soak in, I have 10 russians and have never seen them soaking, they get water from the frozen vegtables and greens you should be feeding them.
Water and high humidity (outdoor pens that are wet) will promote shell rot of typres or skin conditions.