Just bought an Aquaclear 70 (300 ) for my 29 gallon tank. Will this be too much filteration for the tank? The tank has about 15 guppies, a mollie and 5 neons. Also my tank hood cracked where you lift the hood up. Anyone know where I could get just the hood without the light. My light is just fine. Would hate to go spend another 30 to $40 for a full hood. Also have a few guppies that look funny. They seem to have a dip in their back. Other than looking funny they seem ok. Had them from birth. Anyone else ever seen guppies like that?