Originally Posted by findad
In my experience, if it looks good and did not leak before, leave it alone. If it is unsightly, trim it out, clean the corners and re-seal it. Use caution not to cut too deep in the corners.
As for heaters, I think a lot of people are moving toward 2 undersized heaters...
That way if one goes out.. you still have one going.
Or if one starts overheating (which they do from time to time)since it is undersized it shouldn't have disastrous effects on your tank.