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Hello, I'm new to "Fish stuff" and currently I have 3, 10 gallon tank's 1 W/ a Red eared Slider (Tortoise) 1 Empty 1 W/ a Female guppy All 3 have filter's and PH balance and everything is perfect. So My question is,  In My 10 gallon tank W/ a Female guppy I have a 30 gallon tank filter on...