While drilling my 90g to put in an overflow, the drilled kicked, I put too much pressure and this was the end result… Is it worth it to just replace the panel?
Unfortunately, even if that small crack wouldn't spread, you will have a very hard time getting the bulkhead to seal with a chip of that size. I'd say do it right and replace the panel as hard as that is to swallow.
While drilling my 90g to put in an overflow, the drilled kicked, I put too much pressure and this was the end result… Is it worth it to just replace the panel?
It’s 90 gallons of water and those chips and cracks are just stress risers for that panel to fail. I wouldn’t mess around unless you want to be renovating a part of your house. Be careful here and just replace the panel.
Look at the bright side, at least you’re not posting 3 months from now learning how to salvage the live stock that spewed out of a 90g tank with a busted panel!