I have a 75 Gallon rimmed tank that I've discovered is about 1/4th inch off level from the front to back. (measured the difference in space between waterline to rim). When I use my bubble level, the bubble does not touch the guide line, but is a little too close for my own sanity. Is this an acceptable amount of "off level" or would it be better to shim it? The tank is stocked, so I just wanted to get some other thoughts before I drained the tank 90% or more. Thanks in advance!
